fix(deps): update dependency @google-cloud/common to ^0.28.0 (#197)

Author: renovate[bot]

packages/google-cloud-dns/package.json

@@ -44,7 +44,7 @@
     "pretest": "npm run compile"
   },
   "dependencies": {
-    "@google-cloud/common": "^0.27.0",
+    "@google-cloud/common": "^0.28.0",
     "@google-cloud/paginator": "^0.1.0",
     "@google-cloud/promisify": "^0.3.0",
     "arrify": "^1.0.1",