build(deps-dev): bump typescript-eslint in /atciss-frontend

Bumps [typescript-eslint](https://github.com/typescript-eslint/typescript-eslint/tree/HEAD/packages/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
...

Signed-off-by: dependabot[bot] <support@github.com>

atciss-frontend/package.json

@@ -45,7 +45,7 @@
                 "prettier-config-nick": "^1.0.2",
                 "sass": "^1.83.4",
                 "typescript": "^5.7.3",
-                "typescript-eslint": "^8.20.0",
+                "typescript-eslint": "^8.21.0",
                 "vite": "^6.0.10",
                 "vitest": "^3.0.2"
         },