Use the public maven central relase of com.google.api.grpc:proto-google-common-protos

This fixes an issue of duplicate and possibly incompatible classes for
com/google/api and com/google/rpc proto generated classes. If a project
includes both api and proto-google-common-protos dependencies, there
will be duplicate classes on the class path. This is because:
- these classes are vendored in this repo but not declared in the pom
- the version of proto-google-common-protos used is not a public release in maven central

Similar to the issue in envoyproxy#171 that envoyproxy#237 will fix.

Signed-off-by: Preston Bennes <[email protected]>

Author: sfc-gh-pbennes

api/pom.xml

@@ -27,6 +27,12 @@
             <version>${grpc.version}</version>
         </dependency>
 
+        <dependency>
+            <groupId>com.google.api.grpc</groupId>
+            <artifactId>proto-google-common-protos</artifactId>
+            <version>${google-common-protos.version}</version>
+        </dependency>
+
         <dependency>
             <groupId>com.google.protobuf</groupId>
             <artifactId>protobuf-java</artifactId>