chore: release 2.3.1 (#163)

🤖 I have created a release \*beep\* \*boop\*
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### [2.3.1](https://www.github.com/googleapis/nodejs-game-servers/compare/v2.3.0...v2.3.1) (2021-05-20)


### Bug Fixes

* **deps:** require google-gax v2.12.0 ([#162](https://www.github.com/googleapis/nodejs-game-servers/issues/162)) ([546c13d](https://www.github.com/googleapis/nodejs-game-servers/commit/546c13d64abedafd055fad9c118d58750f0f9f25))
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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).

generated,README.md/package.json

@@ -13,7 +13,7 @@
     "test": "c8 mocha --timeout 600000 test/*.js"
   },
   "dependencies": {
-    "@google-cloud/game-servers": "^2.3.0"
+    "@google-cloud/game-servers": "^2.3.1"
   },
   "devDependencies": {
     "c8": "^7.2.1",