Update dependency @reduxjs/toolkit to v2 (#309)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [@reduxjs/toolkit](https://redux-toolkit.js.org) ([source](https://togithub.com/reduxjs/redux-toolkit)) | [`^1.9.2` -> `^2.0.0`](https://renovatebot.com/diffs/npm/@reduxjs%2ftoolkit/1.9.7/2.0.1) | [![age](https://developer.mend.io/api/mc/badges/age/npm/@reduxjs%2ftoolkit/2.0.1?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://developer.mend.io/api/mc/badges/adoption/npm/@reduxjs%2ftoolkit/2.0.1?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://developer.mend.io/api/mc/badges/compatibility/npm/@reduxjs%2ftoolkit/1.9.7/2.0.1?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://developer.mend.io/api/mc/badges/confidence/npm/@reduxjs%2ftoolkit/1.9.7/2.0.1?slim=true)](https://docs.renovatebot.com/merge-confidence/) |

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### Release Notes

<details>
<summary>reduxjs/redux-toolkit (@&#8203;reduxjs/toolkit)</summary>

### [`v2.0.1`](https://togithub.com/reduxjs/redux-toolkit/compare/v2.0.0...v2.0.1)

[Compare Source](https://togithub.com/reduxjs/redux-toolkit/compare/v2.0.0...v2.0.1)

### [`v2.0.0`](https://togithub.com/reduxjs/redux-toolkit/compare/v1.9.7...v2.0.0)

[Compare Source](https://togithub.com/reduxjs/redux-toolkit/compare/v1.9.7...v2.0.0)

</details>

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frontend/package.json

@@ -10,7 +10,7 @@
     "@mui/icons-material": "5.15.0",
     "@mui/material": "5.15.0",
     "@mui/x-date-pickers": "6.18.5",
-    "@reduxjs/toolkit": "^1.9.2",
+    "@reduxjs/toolkit": "^2.0.0",
     "axios": "1.6.2",
     "http-proxy-middleware": "2.0.6",
     "luxon": "3.4.4",