chore: release 2.1.5 (#509)

🤖 I have created a release \*beep\* \*boop\* 
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### [2.1.5](https://github.com/googleapis/nodejs-monitoring/compare/v2.1.4...v2.1.5) (2021-01-07)


### Bug Fixes

* update alert policies one at a time because (concurrent updates are not supported) ([#507](https://github.com/googleapis/nodejs-monitoring/issues/507)) ([2bf75a2](https://github.com/googleapis/nodejs-monitoring/commit/2bf75a2294f82d3b75e0ee3d44c91b0b8e5ec358))
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This PR was generated with [Release Please](https://github.com/googleapis/release-please).

monitoring/snippets/package.json

@@ -14,7 +14,7 @@
     "test": "mocha --timeout 600000"
   },
   "dependencies": {
-    "@google-cloud/monitoring": "^2.1.4",
+    "@google-cloud/monitoring": "^2.1.5",
     "yargs": "^16.0.0"
   },
   "devDependencies": {