fix(deps): updates to metadata check to better work in all environments (#581)

Author: Benjamin E. Coe

package.json

@@ -60,8 +60,8 @@
     "arrify": "^2.0.0",
     "eventid": "^0.1.2",
     "extend": "^3.0.2",
-    "gcp-metadata": "^2.0.0",
-    "google-auth-library": "^5.0.0",
+    "gcp-metadata": "^3.0.0",
+    "google-auth-library": "^5.2.2",
     "google-gax": "^1.0.0",
     "is": "^3.2.1",
     "on-finished": "^2.3.0",