chore(deps): update dev dependency postcss to v8.5.8 (#612)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

package-lock.json

@@ -46,7 +46,7 @@
     "eslint": "9.39.4",
     "fastify": "5.7.4",
     "npm-run-all2": "8.0.4",
-    "postcss": "8.5.6",
+    "postcss": "8.5.8",
     "prettier": "3.8.1",
     "rimraf": "6.1.3",
     "rollup": "4.59.0",