Use compact-no-array style for @InlineMe annotations

Suggestions by the `InlineMeSuggester` always use the array syntax for import annotations even when only one import is listed.

This clashes with checkstyle's [`AnnotationUseStyleCheck`](https://checkstyle.sourceforge.io/apidocs/com/puppycrawl/tools/checkstyle/checks/annotation/AnnotationUseStyleCheck.html) check which uses `COMPACT_NO_ARRAY` style per default and disallows single-value arrays. Note that the proposed style would also work with the two other checkstyle options.

Example:

```diff
- @InlineMe(replacement = "REPLACEMENT", "imports = {"java.time.Duration"})
+ @InlineMe(replacement = "REPLACEMENT", "imports = "java.time.Duration")
```

Note that this is a more nitty suggestion -- fine to drop this if the other style is preferred. But I believe this would reduce friction for consumers using checkstyle.

Fixes #2366

COPYBARA_INTEGRATE_REVIEW=#2366 from fawind:fw/inlineme-compact-no-array 6af0ad6
PiperOrigin-RevId: 376748570

core/src/main/java/com/google/errorprone/bugpatterns/inlineme/InlineMeData.java

@@ -83,7 +83,11 @@ String buildAnnotation() {
   }
 
   private static String quote(Set<String> imports) {
-    return "{\"" + Joiner.on("\", \"").join(imports) + "\"}";
+    String quoted = "\"" + Joiner.on("\", \"").join(imports) + "\"";
+    if (imports.size() == 1) {
+      return quoted;
+    }
+    return "{" + quoted + "}";
   }
 
   // TODO(glorioso): be tolerant of trailing semicolon

core/src/test/java/com/google/errorprone/bugpatterns/inlineme/SuggesterTest.java

@@ -42,6 +42,15 @@ public void testBuildAnnotation_withImports() {
                 + "imports = {\"java.time.Duration\", \"java.time.Instant\"})\n");
   }
 
+  @Test
+  public void testBuildAnnotation_withSingleImport() {
+    assertThat(
+            InlineMeData.buildAnnotation(
+                "REPLACEMENT", ImmutableSet.of("java.time.Duration"), ImmutableSet.of()))
+        .isEqualTo(
+            "@InlineMe(replacement = \"REPLACEMENT\", " + "imports = \"java.time.Duration\")\n");
+  }
+
   @Test
   public void testInstanceMethodNewImport() {
     refactoringTestHelper
@@ -67,7 +76,7 @@ public void testInstanceMethodNewImport() {
             "public final class Client {",
             "  private Duration deadline = Duration.ofSeconds(5);",
             "  @InlineMe(replacement = \"this.setDeadline(Duration.ofMillis(millis))\","
-                + " imports = {\"java.time.Duration\"})",
+                + " imports = \"java.time.Duration\")",
             "  @Deprecated",
             "  public void setDeadline(long millis) {",
             "    setDeadline(Duration.ofMillis(millis));",
@@ -100,7 +109,7 @@ public void testStaticMethodInNewClass() {
             "public final class Client {",
             "  @InlineMe(",
             "      replacement = \"Duration.ofMillis(millis)\", ",
-            "      imports = {\"java.time.Duration\"})",
+            "      imports = \"java.time.Duration\")",
             "  @Deprecated",
             "  public Duration fromMillis(long millis) {",
             "    return Duration.ofMillis(millis);",
@@ -142,7 +151,7 @@ public void testReturnField() {
             "import com.google.errorprone.annotations.InlineMe;",
             "import java.time.Duration;",
             "public final class Client {",
-            "  @InlineMe(replacement = \"Duration.ZERO\", imports = {\"java.time.Duration\"})",
+            "  @InlineMe(replacement = \"Duration.ZERO\", imports = \"java.time.Duration\")",
             "  @Deprecated",
             "  public Duration getZero() {",
             "    return Duration.ZERO;",
@@ -230,7 +239,7 @@ public void testMethodReference() {
             "import java.util.Optional;",
             "public final class Client {",
             "  @InlineMe(replacement = \"input.map(Duration::ofMillis)\", ",
-            "      imports = {\"java.time.Duration\"})",
+            "      imports = \"java.time.Duration\")",
             "  @Deprecated",
             "  public Optional<Duration> silly(Optional<Long> input) {",
             "    return input.map(Duration::ofMillis);",
@@ -258,7 +267,7 @@ public void testNewClass() {
             "import com.google.errorprone.annotations.InlineMe;",
             "import org.joda.time.Instant;",
             "public final class Client {",
-            "  @InlineMe(replacement = \"new Instant()\", imports = {\"org.joda.time.Instant\"})",
+            "  @InlineMe(replacement = \"new Instant()\", imports = \"org.joda.time.Instant\")",
             "  @Deprecated",
             "  public Instant silly() {",
             "    return new Instant();",
@@ -286,7 +295,7 @@ public void testNewArray() {
             "import com.google.errorprone.annotations.InlineMe;",
             "import org.joda.time.Instant;",
             "public final class Client {",
-            "  @InlineMe(replacement = \"new Instant[42]\", imports = {\"org.joda.time.Instant\"})",
+            "  @InlineMe(replacement = \"new Instant[42]\", imports = \"org.joda.time.Instant\")",
             "  @Deprecated",
             "  public Instant[] silly() {",
             "    return new Instant[42];",
@@ -314,7 +323,7 @@ public void testNewNestedClass() {
             "import com.google.errorprone.annotations.InlineMe;",
             "public final class Client {",
             "  @InlineMe(replacement = \"new NestedClass()\", ",
-            "      imports = {\"com.google.frobber.Client.NestedClass\"})",
+            "      imports = \"com.google.frobber.Client.NestedClass\")",
             "  @Deprecated",
             "  public NestedClass silly() {",
             "    return new NestedClass();",
@@ -499,7 +508,7 @@ public void testWithCast() {
             "import java.time.Duration;",
             "public final class Client {",
             "  @InlineMe(replacement = \"this.foo((Duration) duration)\", imports ="
-                + " {\"java.time.Duration\"})",
+                + " \"java.time.Duration\")",
             "  @Deprecated",
             "  public void setDuration(Object duration) {",
             "    foo((Duration) duration);",
@@ -626,7 +635,7 @@ public void testTernaryOverMultipleLines() {
             "public final class Client {",
             "  @InlineMe(replacement = \""
                 + "deadline.compareTo(Duration.ZERO) > 0 ? deadline : Duration.ZERO\", ",
-            "imports = {\"java.time.Duration\"})",
+            "imports = \"java.time.Duration\")",
             "  @Deprecated",
             "  public Duration getDeadline(Duration deadline) {",
             "    return deadline.compareTo(Duration.ZERO) > 0",
@@ -660,7 +669,7 @@ public void testStaticCallingAnotherQualifiedStatic() {
             "import java.time.Duration;",
             "public final class Client {",
             "  @InlineMe(replacement = \"Client.getDeadline2()\", ",
-            "      imports = {\"com.google.frobber.Client\"})",
+            "      imports = \"com.google.frobber.Client\")",
             "  @Deprecated",
             "  public static Duration getDeadline() {",
             "    return Client.getDeadline2();",
@@ -692,7 +701,7 @@ public void staticReferenceToJavaLang() {
             "import com.google.errorprone.annotations.InlineMe;",
             "public final class Client {",
             "  @InlineMe(replacement = \"format(template, arg)\", staticImports ="
-                + " {\"java.lang.String.format\"})",
+                + " \"java.lang.String.format\")",
             "  @Deprecated",
             "  public static String myFormat(String template, String arg) {",
             "    return format(template, arg);",
@@ -723,7 +732,7 @@ public void replacementContainsGenericInvocation() {
             "import java.util.List;",
             "public final class Client {",
             "  @InlineMe(replacement = \"new ArrayList<Void>()\", imports ="
-                + " {\"java.util.ArrayList\"})",
+                + " \"java.util.ArrayList\")",
             "  @Deprecated",
             "  public static List<Void> newArrayList() {",
             "    return new ArrayList<Void>();",