deps: update dependency com.google.auth:google-auth-library-bom to v1.8.1 (#742)

Author: renovate-bot

first-party-dependencies/pom.xml

@@ -63,7 +63,7 @@
     <google.api-common.version>2.2.1</google.api-common.version>
     <google.common-protos.version>2.9.2</google.common-protos.version>
     <google.core.version>2.8.1</google.core.version>
-    <google.auth.version>1.8.0</google.auth.version>
+    <google.auth.version>1.8.1</google.auth.version>
     <google.http-client.version>1.42.1</google.http-client.version>
     <google.oauth-client.version>1.34.1</google.oauth-client.version>
     <google.api-client.version>1.35.2</google.api-client.version>