Bump protobuf-java from 2.5.0 to 3.16.3

Bumps [protobuf-java](https://github.com/protocolbuffers/protobuf) from 2.5.0 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/v2.5.0...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 d3b02c8..06c5a35 100644
--- a/pom.xml
+++ b/pom.xml
@@ -101,7 +101,7 @@
 
     <protostuff.version>1.0.7</protostuff.version>
     <msgpack.version>0.6.7</msgpack.version>
-    <protobuf.version>2.5.0</protobuf.version>
+    <protobuf.version>3.16.3</protobuf.version>
     <kryo.version>2.21</kryo.version>
 
     <snakeyaml.version>1.10</snakeyaml.version>