chore(deps): update dependency postcss to v8.5.4 (#4316)

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

Author: renovate[bot]

spring-boot-admin-server-ui/package-lock.json

@@ -92,7 +92,7 @@
     "jsdom": "^26.0.0",
     "msw": "2.8.5",
     "msw-storybook-addon": "2.0.4",
-    "postcss": "8.5.3",
+    "postcss": "8.5.4",
     "prettier": "^3.0.3",
     "rollup-plugin-visualizer": "6.0.1",
     "sass": "^1.57.1",