Bump wp-cli/language-command from 2.0.20 to 2.0.21

Bumps [wp-cli/language-command](https://github.com/wp-cli/language-command) from 2.0.20 to 2.0.21.
- [Release notes](https://github.com/wp-cli/language-command/releases)
- [Commits](wp-cli/language-command@v2.0.20...v2.0.21)

---
updated-dependencies:
- dependency-name: wp-cli/language-command
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]