fix(deps): roll back dependency @google-cloud/monitoring to ^3.0.3 (#4173)

Author: renovate-bot

packages/google-cloud-monitoring/samples/package.json

@@ -14,7 +14,7 @@
     "test": "mocha --timeout 600000"
   },
   "dependencies": {
-    "@google-cloud/monitoring": "^3.0.4",
+    "@google-cloud/monitoring": "^3.0.3",
     "yargs": "^16.0.0"
   },
   "devDependencies": {