fix(deps): update dependency eslint to v8 (#3625)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [eslint](https://eslint.org) ([source](https://togithub.com/eslint/eslint)) | [`^7.0.0` -> `^8.0.0`](https://renovatebot.com/diffs/npm/eslint/7.32.0/8.29.0) | [![age](https://badges.renovateapi.com/packages/npm/eslint/8.29.0/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/npm/eslint/8.29.0/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/npm/eslint/8.29.0/compatibility-slim/7.32.0)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/npm/eslint/8.29.0/confidence-slim/7.32.0)](https://docs.renovatebot.com/merge-confidence/) |

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packages/google-cloud-servicedirectory/samples/package.json

@@ -14,7 +14,7 @@
   },
   "dependencies": {
     "@google-cloud/service-directory": "^4.0.4",
-    "eslint": "^7.0.0",
+    "eslint": "^8.0.0",
     "json-schema": "^0.4.0",
     "uuid": "^9.0.0"
   },