build(deps-dev): bump @spotify/prettier-config in /microsite

Bumps [@spotify/prettier-config](https://github.com/spotify/web-scripts) from 11.0.0 to 12.0.0.
- [Release notes](https://github.com/spotify/web-scripts/releases)
- [Changelog](https://github.com/spotify/web-scripts/blob/master/CHANGELOG.md)
- [Commits](https://github.com/spotify/web-scripts/compare/v11.0.0...v12.0.0)

---
updated-dependencies:
- dependency-name: "@spotify/prettier-config"
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

microsite/package.json

@@ -16,7 +16,7 @@
     "lock:check": "yarn-lock-check"
   },
   "devDependencies": {
-    "@spotify/prettier-config": "^11.0.0",
+    "@spotify/prettier-config": "^12.0.0",
     "docusaurus": "^2.0.0-alpha.70",
     "js-yaml": "^4.1.0",
     "prettier": "^2.4.1",