Bump protobuf-java from 2.6.1 to 3.16.1 in /java

Bumps [protobuf-java](https://github.com/protocolbuffers/protobuf) from 2.6.1 to 3.16.1.
- [Release notes](https://github.com/protocolbuffers/protobuf/releases)
- [Changelog](https://github.com/protocolbuffers/protobuf/blob/main/generate_changelog.py)
- [Commits](protocolbuffers/protobuf@v2.6.1...v3.16.1)

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

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Author: dependabot[bot]

java/pom.xml

@@ -48,7 +48,7 @@
 	<dependency>
 	    <groupId>com.google.protobuf</groupId>
 	    <artifactId>protobuf-java</artifactId>
-	    <version>2.6.1</version>
+	    <version>3.16.1</version>
 	    <scope>compile</scope>
 	</dependency>
   </dependencies>