build(deps): bump protobuf-java from 3.21.2 to 3.21.7 (#1973)

Bumps [protobuf-java](https://github.com/protocolbuffers/protobuf) from 3.21.2 to 3.21.7.
- [Release notes](https://github.com/protocolbuffers/protobuf/releases)
- [Changelog](https://github.com/protocolbuffers/protobuf/blob/main/generate_changelog.py)
- [Commits](protocolbuffers/protobuf@v3.21.2...v3.21.7)

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

Signed-off-by: dependabot[bot] <support@github.com>

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

pom.xml

@@ -111,7 +111,7 @@
         <hugegraph-rpc.version>2.0.1</hugegraph-rpc.version>
         <hugegraph-common.version>2.1.2</hugegraph-common.version>
         <grpc.version>1.47.0</grpc.version>
-        <protobuf.version>3.21.2</protobuf.version>
+        <protobuf.version>3.21.7</protobuf.version>
     </properties>
     <modules>
         <module>hugegraph-core</module>