Bump @vscode/extension-telemetry from 0.6.2 to 0.8.4

Bumps [@vscode/extension-telemetry](https://github.com/Microsoft/vscode-extension-telemetry) from 0.6.2 to 0.8.4.
- [Release notes](https://github.com/Microsoft/vscode-extension-telemetry/releases)
- [Commits](microsoft/vscode-extension-telemetry@v0.6.2...v0.8.4)

---
updated-dependencies:
- dependency-name: "@vscode/extension-telemetry"
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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