Bump prettier from 2.4.1 to 2.8.2 in /ui

Bumps [prettier](https://github.com/prettier/prettier) from 2.4.1 to 2.8.2.
- [Release notes](https://github.com/prettier/prettier/releases)
- [Changelog](https://github.com/prettier/prettier/blob/main/CHANGELOG.md)
- [Commits](https://github.com/prettier/prettier/compare/2.4.1...2.8.2)

---
updated-dependencies:
- dependency-name: prettier
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

ui/package.json

@@ -44,7 +44,7 @@
     "@testing-library/react-hooks": "^7.0.2",
     "@testing-library/user-event": "^13.5.0",
     "css-mediaquery": "^0.1.2",
-    "prettier": "2.4.1",
+    "prettier": "2.8.2",
     "ra-test": "^3.18.3",
     "workbox-cli": "^6.3.0"
   },