Bump typescript-eslint from 8.20.0 to 8.21.0 in the eslint group

Bumps the eslint group with 1 update: [typescript-eslint](https://github.com/typescript-eslint/typescript-eslint/tree/HEAD/packages/typescript-eslint).


Updates `typescript-eslint` from 8.20.0 to 8.21.0
- [Release notes](https://github.com/typescript-eslint/typescript-eslint/releases)
- [Changelog](https://github.com/typescript-eslint/typescript-eslint/blob/main/packages/typescript-eslint/CHANGELOG.md)
- [Commits](https://github.com/typescript-eslint/typescript-eslint/commits/v8.21.0/packages/typescript-eslint)

---
updated-dependencies:
- dependency-name: typescript-eslint
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: eslint
...

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

package.json

@@ -47,7 +47,7 @@
     "markdownlint-cli2": "^0.17.2",
     "prettier": "^3.4.2",
     "typescript": "~5.7.3",
-    "typescript-eslint": "^8.20.0"
+    "typescript-eslint": "^8.21.0"
   },
   "browserslist": {
     "production": [