chore(deps-dev): bump postcss from 8.5.6 to 8.5.8

Bumps [postcss](https://github.com/postcss/postcss) from 8.5.6 to 8.5.8.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@8.5.6...8.5.8)

---
updated-dependencies:
- dependency-name: postcss
  dependency-version: 8.5.8
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

frontend/package.json

@@ -104,7 +104,7 @@
     "normalize.css": "8.0.1",
     "oxlint": "1.50.0",
     "oxlint-tsgolint": "0.14.2",
-    "postcss": "8.5.6",
+    "postcss": "8.5.8",
     "sass": "1.70.0",
     "solid-js": "1.9.10",
     "subset-font": "2.3.0",