chore: bump @mui/joy in /frontend/extension (#239)

Bumps [@mui/joy](https://github.com/mui/material-ui/tree/HEAD/packages/mui-joy) from 5.0.0-beta.47 to 5.0.0-beta.48.
- [Release notes](https://github.com/mui/material-ui/releases)
- [Changelog](https://github.com/mui/material-ui/blob/next/CHANGELOG.md)
- [Commits](https://github.com/mui/material-ui/commits/HEAD/packages/mui-joy)

---
updated-dependencies:
- dependency-name: "@mui/joy"
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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frontend/extension/package.json

@@ -14,7 +14,7 @@
   "dependencies": {
     "@emotion/react": "^11.11.4",
     "@emotion/styled": "^11.11.5",
-    "@mui/joy": "5.0.0-beta.47",
+    "@mui/joy": "5.0.0-beta.48",
     "@plasmohq/storage": "^1.11.0",
     "axios": "^1.6.8",
     "classnames": "^2.5.1",