chore: release 4.9.0 (#802)

🤖 I have created a release \*beep\* \*boop\*
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## [4.9.0](https://www.github.com/googleapis/nodejs-speech/compare/v4.8.1...v4.9.0) (2021-09-20)


### Features

* add output_config request field ([#801](https://www.github.com/googleapis/nodejs-speech/issues/801)) ([b4f8cbf](https://www.github.com/googleapis/nodejs-speech/commit/b4f8cbff71e3cbdce4d7fb7cbe67f7065f4c6a2b))
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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).

speech/package.json

@@ -15,7 +15,7 @@
     "test": "c8 mocha system-test --timeout 600000"
   },
   "dependencies": {
-    "@google-cloud/speech": "^4.8.1",
+    "@google-cloud/speech": "^4.9.0",
     "@google-cloud/storage": "^5.0.0",
     "chalk": "^4.0.0",
     "node-record-lpcm16": "^1.0.1",