feat: on repo creation a git hook that validates repo before push

[ronantakizawa]

Description (e.g. "Related to ...", etc.)

When running taf repo create, a git hook that validates the repo before pushing is made. Resolves issue #393

Code review checklist (for code reviewer to complete)

• [ ] Pull request represents a single change (i.e. not fixing disparate/unrelated things in a single PR)
• [ ] Title summarizes what is changing
• [ ] Commit messages are meaningful (see this for details)
• [ ] Tests have been included and/or updated, as appropriate
• [ ] Docstrings have been included and/or updated, as appropriate
• [ ] Changelog has been updated, as needed (see CHANGELOG.md)

[renatav]

I was using this today and I think that it's also important to provide some feedback that validation is in progress. A lot of our commands automatically commit and push. Because push is using subprocess (subprocess.run(command, **options)), all of the output we get when we run git push through the command line is not visible. Because validation is started from the first commit if there is no last_validated_commit, it can take a while. It would make sense to check if there is a git hook here and log "Validating and pushing"