maintenance: add auto-updating of npm packages (#1626)

Author: stephenplusplus

handwritten/storage/package.json

@@ -52,9 +52,9 @@
   "dependencies": {
     "@google-cloud/common": "^0.5.0",
     "arrify": "^1.0.0",
-    "async": "^1.4.2",
+    "async": "^2.0.1",
     "concat-stream": "^1.5.0",
-    "create-error-class": "^2.0.1",
+    "create-error-class": "^3.0.2",
     "duplexify": "^3.2.0",
     "extend": "^3.0.0",
     "gcs-resumable-upload": "^0.7.1",