Bump @types/he from 1.2.2 to 1.2.3 in /frontend (#852)

Bumps [@types/he](https://github.com/DefinitelyTyped/DefinitelyTyped/tree/HEAD/types/he) from 1.2.2 to 1.2.3.
- [Release notes](https://github.com/DefinitelyTyped/DefinitelyTyped/releases)
- [Commits](https://github.com/DefinitelyTyped/DefinitelyTyped/commits/HEAD/types/he)

---
updated-dependencies:
- dependency-name: "@types/he"
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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

frontend/package.json

@@ -18,7 +18,7 @@
     "@babel/preset-react": "^7.22.15",
     "@babel/preset-typescript": "^7.23.3",
     "@types/bootstrap": "^4.6.2",
-    "@types/he": "^1.2.2",
+    "@types/he": "^1.2.3",
     "@types/luxon": "^2.4.0",
     "@types/node": "^14.18.63",
     "@types/react": "^16.14.42",