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>

tests/test_utils/test_utils.py

@@ -336,6 +336,21 @@ class TestUtils:
         release = module_build_service.utils.get_rpm_release(build_one)
         assert release == 'module+f28+2+814cfa39'
 
+    def test_get_rpm_release_mse_scratch(self):
+        init_data(contexts=True, scratch=True)
+        build_one = models.ModuleBuild.query.get(2)
+        build_two = models.ModuleBuild.query.get(3)
+        release_one = module_build_service.utils.get_rpm_release(build_one)
+        release_two = module_build_service.utils.get_rpm_release(build_two)
+        assert release_one == "scrmod+2+b8645bbb"
+        assert release_two == "scrmod+2+17e35784"
+
+    def test_get_rpm_release_platform_stream_scratch(self):
+        scheduler_init_data(1, scratch=True)
+        build_one = models.ModuleBuild.query.get(2)
+        release = module_build_service.utils.get_rpm_release(build_one)
+        assert release == 'scrmod+f28+2+814cfa39'
+
     @pytest.mark.parametrize('scmurl', [
         ('https://src.stg.fedoraproject.org/modules/testmodule.git'
          '?#620ec77321b2ea7b0d67d82992dda3e1d67055b4'),