Bump @testing-library/jest-dom in /extensions/ql-vscode (#3368)

Bumps [@testing-library/jest-dom](https://github.com/testing-library/jest-dom) from 6.2.0 to 6.4.2.
- [Release notes](https://github.com/testing-library/jest-dom/releases)
- [Changelog](https://github.com/testing-library/jest-dom/blob/main/CHANGELOG.md)
- [Commits](testing-library/jest-dom@v6.2.0...v6.4.2)

---
updated-dependencies:
- dependency-name: "@testing-library/jest-dom"
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

extensions/ql-vscode/package-lock.json

@@ -1984,7 +1984,7 @@
     "@storybook/react-webpack5": "^7.6.12",
     "@storybook/theming": "^7.6.12",
     "@testing-library/dom": "^9.3.4",
-    "@testing-library/jest-dom": "^6.2.0",
+    "@testing-library/jest-dom": "^6.4.2",
     "@testing-library/react": "^14.0.0",
     "@testing-library/user-event": "^14.5.2",
     "@types/child-process-promise": "^2.2.1",