Bump rgb2hex from 0.1.0 to 0.1.9
Bump rgb2hex from 0.1.0 to 0.1.9

Bumps [rgb2hex](https://github.com/christian-bromann/rgb2hex) from 0.1.0 to 0.1.9.
- [Release notes](https://github.com/christian-bromann/rgb2hex/releases)
- [Commits](https://github.com/christian-bromann/rgb2hex/compare/v0.1.0...v0.1.9)

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>
ggallon/rock,ggallon/rock