chore(deps): bump postcss from 8.4.21 to 8.4.31 in /web

Bumps [postcss](https://github.com/postcss/postcss) from 8.4.21 to 8.4.31.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@8.4.21...8.4.31)

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

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

web/package.json

@@ -24,7 +24,7 @@
     "@tanstack/svelte-table": "^8.8.0",
     "autoprefixer": "^10.4.14",
     "chart.js": "^4.2.1",
-    "postcss": "^8.4.21",
+    "postcss": "^8.4.31",
     "prettier": "^2.8.4",
     "prettier-plugin-svelte": "^2.9.0",
     "prettier-plugin-tailwindcss": "^0.2.5",