build(deps): bump the simple group across 1 directory with 2 updates

Bumps the simple group with 2 updates in the /demo directory: [react-icons](https://github.com/react-icons/react-icons) and [postcss](https://github.com/postcss/postcss).


Updates `react-icons` from 5.3.0 to 5.4.0
- [Release notes](https://github.com/react-icons/react-icons/releases)
- [Commits](react-icons/react-icons@v5.3.0...v5.4.0)

Updates `postcss` from 8.4.49 to 8.5.1
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@8.4.49...8.5.1)

---
updated-dependencies:
- dependency-name: react-icons
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: simple
- dependency-name: postcss
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: simple
...

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

demo/package.json

@@ -19,7 +19,7 @@
     "nanoid": "^5.0.9",
     "react": "^18.3.1",
     "react-dom": "^18.3.1",
-    "react-icons": "^5.3.0"
+    "react-icons": "^5.4.0"
   },
   "devDependencies": {
     "@types/react": "^18.3.3",
@@ -32,7 +32,7 @@
     "eslint-plugin-react-hooks": "^4.6.2",
     "eslint-plugin-react-refresh": "^0.4.7",
     "netlify-cli": "^17.37.2",
-    "postcss": "^8.4.49",
+    "postcss": "^8.5.1",
     "tailwindcss": "^3.4.15",
     "typescript": "^5.4.5",
     "vite": "^5.3.1"