deps: update dependency io.grpc:grpc-bom to v1.34.1 (#342)

Author: renovate-bot

java-core/pom.xml

@@ -158,7 +158,7 @@
     <google.auth.version>0.22.0</google.auth.version>
     <google.api.version>1.31.1</google.api.version>
     <google.http.version>1.38.0</google.http.version>
-    <grpc.version>1.33.1</grpc.version>
+    <grpc.version>1.34.1</grpc.version>
     <protobuf.version>3.14.0</protobuf.version>
     <opencensus.version>0.24.0</opencensus.version>
     <annotations-api.version>1.3.2</annotations-api.version>