Bump @wdio/cli from 8.20.2 to 8.21.0

Bumps [@wdio/cli](https://github.com/webdriverio/webdriverio/tree/HEAD/packages/wdio-cli) from 8.20.2 to 8.21.0.
- [Release notes](https://github.com/webdriverio/webdriverio/releases)
- [Changelog](https://github.com/webdriverio/webdriverio/blob/main/CHANGELOG.md)
- [Commits](https://github.com/webdriverio/webdriverio/commits/v8.21.0/packages/wdio-cli)

---
updated-dependencies:
- dependency-name: "@wdio/cli"
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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