common: update google-auto-auth to 0.6.0 (googleapis#2162)

Author: ofrobots

packages/common/package.json

@@ -45,7 +45,7 @@
     "duplexify": "^3.5.0",
     "ent": "^2.2.0",
     "extend": "^3.0.0",
-    "google-auto-auth": "^0.5.2",
+    "google-auto-auth": "^0.6.0",
     "is": "^3.2.0",
     "log-driver": "^1.2.5",
     "methmeth": "^1.1.0",