chore: release 2.1.0 (#40)

🤖 I have created a release \*beep\* \*boop\* 
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## [2.1.0](https://www.github.com/googleapis/nodejs-dialogflow-cx/compare/v2.0.0...v2.1.0) (2020-11-25)


### Features

* add back v3beta1 API surface ([#39](https://www.github.com/googleapis/nodejs-dialogflow-cx/issues/39)) ([36ba8fa](https://www.github.com/googleapis/nodejs-dialogflow-cx/commit/36ba8fa857ae34a21ce0710986689667f909349f))
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This PR was generated with [Release Please](https://github.com/googleapis/release-please).

dialogflow-cx/package.json

@@ -13,7 +13,7 @@
     "test": "c8 mocha --timeout 600000 test/*.js"
   },
   "dependencies": {
-    "@google-cloud/dialogflow-cx": "^2.0.0",
+    "@google-cloud/dialogflow-cx": "^2.1.0",
     "uuid": "^8.3.1"
   },
   "devDependencies": {