deps: update dependency com.google.protobuf:protobuf-bom to v3.21.1

Author: renovate-bot

pom.xml

@@ -159,7 +159,7 @@
     <google.api.version>1.34.1</google.api.version>
     <google.http.version>1.41.8</google.http.version>
     <grpc.version>1.47.0</grpc.version>
-    <protobuf.version>3.21.0</protobuf.version>
+    <protobuf.version>3.21.1</protobuf.version>
     <opencensus.version>0.31.1</opencensus.version>
     <annotations-api.version>1.3.2</annotations-api.version>
     <guava.version>31.1-jre</guava.version>