chore(deps): update dependency sinon to v14 (#267)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [sinon](https://sinonjs.org/) ([source](https://github.com/sinonjs/sinon)) | [`^13.0.0` -> `^14.0.0`](https://renovatebot.com/diffs/npm/sinon/13.0.2/14.0.0) | [![age](https://badges.renovateapi.com/packages/npm/sinon/14.0.0/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/npm/sinon/14.0.0/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/npm/sinon/14.0.0/compatibility-slim/13.0.2)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/npm/sinon/14.0.0/confidence-slim/13.0.2)](https://docs.renovatebot.com/merge-confidence/) |

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### Release Notes

<details>
<summary>sinonjs/sinon</summary>

### [`v14.0.0`](https://github.com/sinonjs/sinon/blob/HEAD/CHANGES.md#&#8203;1400)

[Compare Source](https://github.com/sinonjs/sinon/compare/v13.0.2...v14.0.0)

-   [`c2bbd826`](https://github.com/sinonjs/sinon/commit/c2bbd82641444eb5b32822489ae40f185afbbf00)
    Drop node 12 (Morgan Roderick)
    > And embrace Node 18
    >
    > See https://nodejs.org/en/about/releases/

*Released by Morgan Roderick on 2022-05-07.*

</details>

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packages/google-cloud-dialogflow-cx/package.json

@@ -65,7 +65,7 @@
     "mocha": "^8.1.1",
     "null-loader": "^4.0.0",
     "pack-n-play": "^1.0.0-2",
-    "sinon": "^13.0.0",
+    "sinon": "^14.0.0",
     "ts-loader": "^9.0.0",
     "typescript": "^3.9.7",
     "webpack": "^5.0.0",