Update dependency postcss-cli to v11 (#109)

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

Author: renovate[bot]

package-lock.json

@@ -64,7 +64,7 @@
     "marked": "^5.0.0",
     "npm-run-all": "^4.1.3",
     "onchange": "^7.0.0",
-    "postcss-cli": "^10.0.0",
+    "postcss-cli": "^11.0.0",
     "postcss-import": "^15.1.0",
     "postcss-nesting": "^12.0.0",
     "prettier": "^3.0.0",