Bump @oclif/plugin-warn-if-update-available from 3.1.19 to 3.1.20

Bumps [@oclif/plugin-warn-if-update-available](https://github.com/oclif/plugin-warn-if-update-available) from 3.1.19 to 3.1.20.
- [Release notes](https://github.com/oclif/plugin-warn-if-update-available/releases)
- [Changelog](https://github.com/oclif/plugin-warn-if-update-available/blob/main/CHANGELOG.md)
- [Commits](oclif/plugin-warn-if-update-available@3.1.19...3.1.20)

---
updated-dependencies:
- dependency-name: "@oclif/plugin-warn-if-update-available"
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]