chore:(deps): bump @testing-library/react in /explorer (#18167)

Bumps [@testing-library/react](https://github.com/testing-library/react-testing-library) from 11.2.7 to 12.0.0.
- [Release notes](https://github.com/testing-library/react-testing-library/releases)
- [Changelog](https://github.com/testing-library/react-testing-library/blob/main/CHANGELOG.md)
- [Commits](testing-library/react-testing-library@v11.2.7...v12.0.0)

---
updated-dependencies:
- dependency-name: "@testing-library/react"
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

explorer/package.json

@@ -11,7 +11,7 @@
     "@solana/spl-token-registry": "^0.2.146",
     "@solana/web3.js": "^1.18.0",
     "@testing-library/jest-dom": "^5.14.1",
-    "@testing-library/react": "^11.2.7",
+    "@testing-library/react": "^12.0.0",
     "@testing-library/user-event": "^13.1.9",
     "@types/bn.js": "^5.1.0",
     "@types/bs58": "^4.0.1",