Add question about which git platform to use

[CasperWA]

Whether or not to use GitHub, GitLab, BitBucket, etc.
This could then match up with a post-hook script to remove the non-chosen platform-specific CI/CD workflow configurations from the generated repository.

And if no platform is chosen, it should either remove all of the configurations or keep them all - this could depend on a second question or it could just work in one way or another. This should be further discussed here and decided upon.