Bump protobuf-java from 3.8.0 to 3.16.3

Bumps [protobuf-java](https://github.com/protocolbuffers/protobuf) from 3.8.0 to 3.16.3.
- [Release notes](https://github.com/protocolbuffers/protobuf/releases)
- [Changelog](https://github.com/protocolbuffers/protobuf/blob/main/generate_changelog.py)
- [Commits](https://github.com/protocolbuffers/protobuf/compare/v3.8.0...v3.16.3)

---
updated-dependencies:
- dependency-name: com.google.protobuf:protobuf-java
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>
diff --git a/pom.xml b/pom.xml
index 15839cb..75c8d1c 100644
--- a/pom.xml
+++ b/pom.xml
@@ -41,7 +41,7 @@
         <prometheus.version>0.12.0</prometheus.version>
         <grpc-java.version>1.24.0</grpc-java.version>
         <proto-google-common-protos.version>1.17.0</proto-google-common-protos.version>
-        <protobuf-java.version>3.8.0</protobuf-java.version>
+        <protobuf-java.version>3.16.3</protobuf-java.version>
         <protoc-gen-grpc-java.version>1.24.0</protoc-gen-grpc-java.version>
         <rpc-grpc-impl.version>1.3.8</rpc-grpc-impl.version>
         <guava.version>30.1-jre</guava.version>