Bump @material-ui/core from 4.11.3 to 4.12.3 in /ui

Bumps [@material-ui/core](https://github.com/mui-org/material-ui/tree/HEAD/packages/material-ui) from 4.11.3 to 4.12.3.
- [Release notes](https://github.com/mui-org/material-ui/releases)
- [Changelog](https://github.com/mui-org/material-ui/blob/v4.12.3/CHANGELOG.md)
- [Commits](https://github.com/mui-org/material-ui/commits/v4.12.3/packages/material-ui)

---
updated-dependencies:
- dependency-name: "@material-ui/core"
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

ui/package.json

@@ -3,10 +3,10 @@
   "version": "0.1.0",
   "private": true,
   "dependencies": {
-    "@material-ui/core": "4.11.3",
+    "@material-ui/core": "4.12.3",
     "@material-ui/icons": "4.11.2",
     "@material-ui/lab": "4.0.0-alpha.57",
-    "@reduxjs/toolkit": "1.5.1",
+    "@reduxjs/toolkit": "1.6.1",
     "@testing-library/jest-dom": "^5.12.0",
     "@testing-library/react": "^11.2.6",
     "@testing-library/user-event": "^13.1.9",