chore(deps-dev): bump postcss from 8.5.6 to 8.5.19

Bumps [postcss](https://github.com/postcss/postcss) from 8.5.6 to 8.5.19.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@8.5.6...8.5.19)

---
updated-dependencies:
- dependency-name: postcss
  dependency-version: 8.5.19
  dependency-type: direct:development
...

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

Author: dependabot[bot]

package-lock.json

@@ -141,7 +141,7 @@
     "karma-spec-reporter": "^0.0.36",
     "lit-html": "^3.2.1",
     "ng-packagr": "^21.0.0",
-    "postcss": "^8.5.1",
+    "postcss": "^8.5.19",
     "postcss-scss": "^4.0.6",
     "prettier": "^3.3.3",
     "puppeteer": "^24.5.0",