chore: release 2.4.0 (#465)

🤖 I have created a release \*beep\* \*boop\*
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## [2.4.0](https://www.github.com/googleapis/nodejs-cloud-container/compare/v2.3.2...v2.4.0) (2021-07-09)


### Features

* allow updating security group on existing clusters ([#464](https://www.github.com/googleapis/nodejs-cloud-container/issues/464)) ([ed09e02](https://www.github.com/googleapis/nodejs-cloud-container/commit/ed09e028126d308cf131f26453fe6c73a73cec6d))
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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).

container/snippets/package.json

@@ -14,7 +14,7 @@
     "test": "mocha system-test --timeout 10000"
   },
   "dependencies": {
-    "@google-cloud/container": "^2.3.2"
+    "@google-cloud/container": "^2.4.0"
   },
   "devDependencies": {
     "chai": "^4.2.0",