Bump vscode-extension-tester from 5.10.0 to 6.0.0

Bumps [vscode-extension-tester](https://github.com/redhat-developer/vscode-extension-tester) from 5.10.0 to 6.0.0.
- [Release notes](https://github.com/redhat-developer/vscode-extension-tester/releases)
- [Changelog](https://github.com/redhat-developer/vscode-extension-tester/blob/main/CHANGELOG.md)
- [Commits](redhat-developer/vscode-extension-tester@v5.10.0...v6.0.0)

---
updated-dependencies:
- dependency-name: vscode-extension-tester
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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Author: dependabot[bot]