Bump prettier from 2.3.2 to 2.4.0 in /ui (#1341)

Bumps [prettier](https://github.com/prettier/prettier) from 2.3.2 to 2.4.0.
- [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/2.3.2...2.4.0)

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

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

ui/package.json

@@ -42,7 +42,7 @@
     "@testing-library/react-hooks": "^7.0.2",
     "@testing-library/user-event": "^13.2.1",
     "css-mediaquery": "^0.1.2",
-    "prettier": "2.3.2",
+    "prettier": "2.4.0",
     "ra-test": "^3.18.0"
   },
   "scripts": {