Add missing @nullable annotations in ContentDisposition.Builder

Closes gh-30820

spring-web/src/main/java/org/springframework/http/ContentDisposition.java

@@ -704,7 +704,7 @@ public interface Builder {
 		/**
 		 * Set the value of the {@literal name} parameter.
 		 */
-		Builder name(String name);
+		Builder name(@Nullable String name);
 
 		/**
 		 * Set the value of the {@literal filename} parameter. The given
@@ -713,7 +713,7 @@ public interface Builder {
 		 * be escaped with a backslash, e.g. {@code "foo\"bar.txt"} becomes
 		 * {@code "foo\\\"bar.txt"}.
 		 */
-		Builder filename(String filename);
+		Builder filename(@Nullable String filename);
 
 		/**
 		 * Set the value of the {@code filename} that will be encoded as
@@ -724,7 +724,7 @@ public interface Builder {
 		 * <a href="https://tools.ietf.org/html/rfc7578#section-4.2">RFC 7578, Section 4.2</a>
 		 * and also RFC 5987 mention it does not apply to multipart requests.
 		 */
-		Builder filename(String filename, Charset charset);
+		Builder filename(@Nullable String filename, @Nullable Charset charset);
 
 		/**
 		 * Set the value of the {@literal size} parameter.
@@ -733,7 +733,7 @@ public interface Builder {
 		 * to be removed in a future release.
 		 */
 		@Deprecated
-		Builder size(Long size);
+		Builder size(@Nullable Long size);
 
 		/**
 		 * Set the value of the {@literal creation-date} parameter.
@@ -742,7 +742,7 @@ public interface Builder {
 		 * to be removed in a future release.
 		 */
 		@Deprecated
-		Builder creationDate(ZonedDateTime creationDate);
+		Builder creationDate(@Nullable ZonedDateTime creationDate);
 
 		/**
 		 * Set the value of the {@literal modification-date} parameter.
@@ -751,7 +751,7 @@ public interface Builder {
 		 * to be removed in a future release.
 		 */
 		@Deprecated
-		Builder modificationDate(ZonedDateTime modificationDate);
+		Builder modificationDate(@Nullable ZonedDateTime modificationDate);
 
 		/**
 		 * Set the value of the {@literal read-date} parameter.
@@ -760,7 +760,7 @@ public interface Builder {
 		 * to be removed in a future release.
 		 */
 		@Deprecated
-		Builder readDate(ZonedDateTime readDate);
+		Builder readDate(@Nullable ZonedDateTime readDate);
 
 		/**
 		 * Build the content disposition.