Merge pull request #1025 from kubernetes-client/dependabot/maven/com.google.protobuf-protobuf-java-3.12.2

Bump protobuf-java from 3.4.0 to 3.12.2

Author: k8s-ci-robot

pom.xml

@@ -38,7 +38,7 @@
     <snakeyaml.version>1.25</snakeyaml.version>
     <slf4j.version>1.7.30</slf4j.version>
     <guava.version>29.0-jre</guava.version>
-    <protobuf.version>3.4.0</protobuf.version>
+    <protobuf.version>3.12.2</protobuf.version>
     <junit.version>4.12</junit.version>
     <bucket4j.version>4.10.0</bucket4j.version>
     <bouncycastle.version>1.65</bouncycastle.version>