Module scratch build fixups per PR review feedback:
- Keep scratch module builds in the 'done' state.
- Make koji tagging for scratch modules unique so the same
commit can be resubmitted.
- Use alternate prefix for scratch module build components so they can
be identified later.
- Prevent scratch build components from being reused.
- Assorted code and comment cleanup.
Signed-off-by: Merlin Mathesius <mmathesi@redhat.com>