chore(deps): bump react from 19.1.1 to 19.2.0 in /testsite

Bumps [react](https://github.com/facebook/react/tree/HEAD/packages/react) from 19.1.1 to 19.2.0.
- [Release notes](https://github.com/facebook/react/releases)
- [Changelog](https://github.com/facebook/react/blob/main/CHANGELOG.md)
- [Commits](https://github.com/facebook/react/commits/v19.2.0/packages/react)

---
updated-dependencies:
- dependency-name: react
  dependency-version: 19.2.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

testsite/package-lock.json

@@ -23,7 +23,7 @@
     "js-base64": "^3.7.8",
     "json-schema-faker": "^0.5.9",
     "jsonpos": "^4.1.2",
-    "react": "^19.1.1",
+    "react": "^19.2.0",
     "react-dom": "^19.1.0",
     "react-markdown": "^10.0.0",
     "react-toastify": "^11.0.3"