deps: update gax to v1.57.0 (#73)

Author: renovate-bot

pom.xml

@@ -56,7 +56,7 @@
     <site.installationModule>${project.artifactId}</site.installationModule>
 
     <grpc.version>1.30.0</grpc.version>
-    <gax.version>1.56.0</gax.version>
+    <gax.version>1.57.0</gax.version>
     <guava.version>29.0-android</guava.version>
     <protobuf.version>3.12.2</protobuf.version>
     <google.api-common.version>1.9.2</google.api-common.version>