chore(deps-dev): bump postcss from 8.5.8 to 8.5.15 (#850)

Bumps [postcss](https://github.com/postcss/postcss) from 8.5.8 to 8.5.15.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@8.5.8...8.5.15)

---
updated-dependencies:
- dependency-name: postcss
  dependency-version: 8.5.15
  dependency-type: direct:development
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

package-lock.json

@@ -52,7 +52,7 @@
     "nodemon": "3.1.14",
     "npm-run-all2": "8.0.4",
     "plugin-node-patternlab-inline-remote-assets": "^0.2.1",
-    "postcss": "^8.5.8",
+    "postcss": "^8.5.15",
     "prettier": "3.7.4",
     "sass": "^1.93.3",
     "style-dictionary": "3.9.2",