Bump postcss from 8.4.40 to 8.5.1

Bumps [postcss](https://github.com/postcss/postcss) from 8.4.40 to 8.5.1.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@8.4.40...8.5.1)

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

Signed-off-by: dependabot[bot] <[email protected]>

package.json

@@ -40,7 +40,7 @@
     "eslint": "^8.57.0",
     "eslint-plugin-jest": "^28.10.0",
     "eslint-plugin-svelte": "^2.39.0",
-    "postcss": "^8.4.38",
+    "postcss": "^8.5.1",
     "prettier": "3.3.3",
     "prettier-plugin-astro": "^0.14.1",
     "prettier-plugin-svelte": "^3.2.8",