fix(deps): update dependency google-auth-library to v5 (#539)

Author: renovate-bot

package.json

@@ -61,7 +61,7 @@
     "eventid": "^0.1.2",
     "extend": "^3.0.2",
     "gcp-metadata": "^2.0.0",
-    "google-auth-library": "^4.0.0",
+    "google-auth-library": "^5.0.0",
     "google-gax": "^1.0.0",
     "is": "^3.2.1",
     "on-finished": "^2.3.0",