Bump postcss from 8.5.16 to 8.5.18 in the all-dependencies group

Bumps the all-dependencies group with 1 update: [postcss](https://github.com/postcss/postcss).


Updates `postcss` from 8.5.16 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@8.5.16...8.5.18)

---
updated-dependencies:
- dependency-name: postcss
  dependency-version: 8.5.18
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: all-dependencies
...

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

Author: dependabot[bot]

package-lock.json

@@ -41,7 +41,7 @@
     "hugo-bin": "0.142.0",
     "jquery": "4.0.0",
     "npm-run-all": "4.1.5",
-    "postcss": "8.5.16",
+    "postcss": "8.5.18",
     "postcss-cli": "11.0.1",
     "prettier": "3.9.5",
     "stylelint": "17.14.0",