chore(deps-dev): bump postcss from 8.5.6 to 8.5.18

Bumps [postcss](https://github.com/postcss/postcss) from 8.5.6 to 8.5.18.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@8.5.6...8.5.18)

---
updated-dependencies:
- dependency-name: postcss
  dependency-version: 8.5.18
  dependency-type: direct:development
...

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

Author: dependabot[bot]

apps/desktop/package.json

@@ -42,7 +42,7 @@
     "eslint-plugin-react-refresh": "^0.4.24",
     "globals": "^16.5.0",
     "monaco-editor": "^0.55.1",
-    "postcss": "^8.5.6",
+    "postcss": "^8.5.18",
     "tailwindcss": "3",
     "typescript": "~5.8.3",
     "typescript-eslint": "^8.49.0",