chore: release 2.2.0 (#514)

🤖 I have created a release \*beep\* \*boop\* 
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## [2.2.0](https://www.github.com/googleapis/nodejs-monitoring/compare/v2.1.5...v2.2.0) (2021-01-09)


### Features

* adds style enumeration ([#513](https://www.github.com/googleapis/nodejs-monitoring/issues/513)) ([2ca2169](https://www.github.com/googleapis/nodejs-monitoring/commit/2ca2169553c90a588cc8c7374d4790da3bf122f2))
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This PR was generated with [Release Please](https://github.com/googleapis/release-please). See [documentation](https://github.com/googleapis/release-please#release-please).

monitoring/snippets/package.json

@@ -14,7 +14,7 @@
     "test": "mocha --timeout 600000"
   },
   "dependencies": {
-    "@google-cloud/monitoring": "^2.1.5",
+    "@google-cloud/monitoring": "^2.2.0",
     "yargs": "^16.0.0"
   },
   "devDependencies": {