Update dependency @google-cloud/compute to ^0.12.0 (#1295)

Author: renovate[bot]

functions/scheduleinstance/package.json

@@ -21,7 +21,7 @@
     "sinon": "^7.0.0"
   },
   "dependencies": {
-    "@google-cloud/compute": "^0.11.0",
+    "@google-cloud/compute": "^0.12.0",
     "safe-buffer": "^5.1.2"
   }
 }