Bump @typescript-eslint/eslint-plugin from 4.20.0 to 4.21.0

Bumps [@typescript-eslint/eslint-plugin](https://github.com/typescript-eslint/typescript-eslint/tree/HEAD/packages/eslint-plugin) from 4.20.0 to 4.21.0.
- [Release notes](https://github.com/typescript-eslint/typescript-eslint/releases)
- [Changelog](https://github.com/typescript-eslint/typescript-eslint/blob/master/packages/eslint-plugin/CHANGELOG.md)
- [Commits](https://github.com/typescript-eslint/typescript-eslint/commits/v4.21.0/packages/eslint-plugin)

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

package-lock.json

@@ -410,7 +410,7 @@
     "@types/mocha": "^8.2.2",
     "@types/node": "^14.14.37",
     "@types/vscode": "^1.55.0",
-    "@typescript-eslint/eslint-plugin": "^4.20.0",
+    "@typescript-eslint/eslint-plugin": "^4.21.0",
     "@typescript-eslint/parser": "^4.20.0",
     "eslint": "^7.23.0",
     "glob": "^7.1.6",