chore(main): release 2.8.4-SNAPSHOT (#353)

🤖 I have created a release *beep* *boop*
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### Updating meta-information for bleeding-edge SNAPSHOT release.

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This PR was generated with [Release Please](https://github.com/googleapis/release-please). See [documentation](https://github.com/googleapis/release-please#release-please).

grpc-google-common-protos/pom.xml

@@ -4,13 +4,13 @@
   <modelVersion>4.0.0</modelVersion>
   <groupId>com.google.api.grpc</groupId>
   <artifactId>grpc-google-common-protos</artifactId>
-  <version>2.8.3</version><!-- {x-version-update:proto-google-common-protos:current} -->
+  <version>2.8.4-SNAPSHOT</version><!-- {x-version-update:proto-google-common-protos:current} -->
   <name>grpc-google-common-protos</name>
   <description>GRPC library for grpc-google-common-protos</description>
   <parent>
     <groupId>com.google.api.grpc</groupId>
     <artifactId>google-common-protos-parent</artifactId>
-    <version>2.8.3</version><!-- {x-version-update:proto-google-common-protos:current} -->
+    <version>2.8.4-SNAPSHOT</version><!-- {x-version-update:proto-google-common-protos:current} -->
   </parent>
   <dependencies>
     <dependency>

pom.xml

@@ -4,7 +4,7 @@
   <groupId>com.google.api.grpc</groupId>
   <artifactId>google-common-protos-parent</artifactId>
   <packaging>pom</packaging>
-  <version>2.8.3</version><!-- {x-version-update:proto-google-common-protos:current} -->
+  <version>2.8.4-SNAPSHOT</version><!-- {x-version-update:proto-google-common-protos:current} -->
   <name>Google Common Protos Parent</name>
   <url>https://github.com/googleapis/java-iam</url>
   <description>
@@ -81,7 +81,7 @@
       <dependency>
         <groupId>com.google.api.grpc</groupId>
         <artifactId>grpc-google-common-protos</artifactId>
-        <version>2.8.3</version><!-- {x-version-update:grpc-google-common-protos:current} -->
+        <version>2.8.4-SNAPSHOT</version><!-- {x-version-update:grpc-google-common-protos:current} -->
       </dependency>
       <dependency>
         <groupId>io.grpc</groupId>
@@ -93,7 +93,7 @@
       <dependency>
         <groupId>com.google.api.grpc</groupId>
         <artifactId>proto-google-common-protos</artifactId>
-        <version>2.8.3</version><!-- {x-version-update:proto-google-common-protos:current} -->
+        <version>2.8.4-SNAPSHOT</version><!-- {x-version-update:proto-google-common-protos:current} -->
       </dependency>
       <dependency>
         <groupId>com.google.guava</groupId>

proto-google-common-protos/pom.xml

@@ -3,13 +3,13 @@
   <modelVersion>4.0.0</modelVersion>
   <groupId>com.google.api.grpc</groupId>
   <artifactId>proto-google-common-protos</artifactId>
-  <version>2.8.3</version><!-- {x-version-update:proto-google-common-protos:current} -->
+  <version>2.8.4-SNAPSHOT</version><!-- {x-version-update:proto-google-common-protos:current} -->
   <name>proto-google-common-protos</name>
   <description>PROTO library for proto-google-common-protos</description>
   <parent>
     <groupId>com.google.api.grpc</groupId>
     <artifactId>google-common-protos-parent</artifactId>
-    <version>2.8.3</version><!-- {x-version-update:proto-google-common-protos:current} -->
+    <version>2.8.4-SNAPSHOT</version><!-- {x-version-update:proto-google-common-protos:current} -->
   </parent>
   <dependencies>
     <dependency>

versions.txt

@@ -1,5 +1,5 @@
 # Format:
 # module:released-version:current-version
 
-proto-google-common-protos:2.8.3:2.8.3
-grpc-google-common-protos:2.8.3:2.8.3
+proto-google-common-protos:2.8.3:2.8.4-SNAPSHOT
+grpc-google-common-protos:2.8.3:2.8.4-SNAPSHOT