deps: update core dependencies (#143)

Author: renovate-bot

pom.xml

@@ -152,14 +152,14 @@
     <github.global.server>github</github.global.server>
     <site.installationModule>google-cloud-core-parent</site.installationModule>
 
-    <gax.version>1.53.0</gax.version>
+    <gax.version>1.53.1</gax.version>
     <google.api-common.version>1.8.1</google.api-common.version>
     <google.common-protos.version>1.17.0</google.common-protos.version>
     <google.iam.version>0.13.0</google.iam.version>
     <google.auth.version>0.20.0</google.auth.version>
     <google.api.version>1.30.7</google.api.version>
     <google.http.version>1.34.1</google.http.version>
-    <grpc.version>1.26.0</grpc.version>
+    <grpc.version>1.27.0</grpc.version>
     <protobuf.version>3.11.1</protobuf.version>
     <opencensus.version>0.24.0</opencensus.version>
     <annotations-api.version>1.3.2</annotations-api.version>