Bump postcss from 8.4.24 to 8.4.31 in /lib/SvelteUi/app

Bumps [postcss](https://github.com/postcss/postcss) from 8.4.24 to 8.4.31.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](https://github.com/postcss/postcss/compare/8.4.24...8.4.31)

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

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

lib/SvelteUi/app/package.json

@@ -13,7 +13,7 @@
     "@tailwindcss/forms": "^0.5.2",
     "autoprefixer": "^10.4.7",
     "http-proxy-middleware": "^2.0.1",
-    "postcss": "^8.4.14",
+    "postcss": "^8.4.31",
     "postcss-load-config": "^4.0.1",
     "svelte": "^3.49.0",
     "svelte-navigator": "^3.2.2",