Bump the dev-dependencies group with 3 updates (#6643)

Bumps the dev-dependencies group with 3 updates: [eslint](https://github.com/eslint/eslint), [i18next](https://github.com/i18next/i18next) and [react-router-dom](https://github.com/remix-run/react-router/tree/HEAD/packages/react-router-dom).


Updates `eslint` from 9.9.1 to 9.10.0
- [Release notes](https://github.com/eslint/eslint/releases)
- [Changelog](https://github.com/eslint/eslint/blob/main/CHANGELOG.md)
- [Commits](https://github.com/eslint/eslint/compare/v9.9.1...v9.10.0)

Updates `i18next` from 23.14.0 to 23.15.0
- [Release notes](https://github.com/i18next/i18next/releases)
- [Changelog](https://github.com/i18next/i18next/blob/master/CHANGELOG.md)
- [Commits](https://github.com/i18next/i18next/compare/v23.14.0...v23.15.0)

Updates `react-router-dom` from 6.26.1 to 6.26.2
- [Release notes](https://github.com/remix-run/react-router/releases)
- [Changelog](https://github.com/remix-run/react-router/blob/main/packages/react-router-dom/CHANGELOG.md)
- [Commits](https://github.com/remix-run/react-router/commits/react-router-dom@6.26.2/packages/react-router-dom)

---
updated-dependencies:
- dependency-name: eslint
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: dev-dependencies
- dependency-name: i18next
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: dev-dependencies
- dependency-name: react-router-dom
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: dev-dependencies
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

src/package.json

@@ -99,7 +99,7 @@
     "@types/supertest": "^6.0.2",
     "@types/underscore": "^1.11.15",
     "chokidar": "^3.6.0",
-    "eslint": "^9.9.1",
+    "eslint": "^9.10.0",
     "eslint-config-etherpad": "^4.0.4",
     "etherpad-cli-client": "^3.0.2",
     "mocha": "^10.7.3",