Bump phan/phan from 2.5.0 to 2.6.0

Bumps [phan/phan](https://github.com/phan/phan) from 2.5.0 to 2.6.0.
- [Release notes](https://github.com/phan/phan/releases)
- [Changelog](https://github.com/phan/phan/blob/master/NEWS.md)
- [Commits](https://github.com/phan/phan/compare/2.5.0...2.6.0

)

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