AttributeError: 'GitBranchModel' object has no attribute 'commit_sha'

[sentry]

Sentry Issue: PCKT-002-PACKIT-SERVICE-8N8

AttributeError: 'GitBranchModel' object has no attribute 'commit_sha'
(6 additional frame(s) were not displayed)
...
  File "packit_service/worker/handlers/abstract.py", line 247, in run_n_clean
    return self.run()
  File "packit_service/worker/handlers/koji.py", line 134, in run
    return self.koji_build_helper.run_koji_build()
  File "packit_service/worker/helpers/build/koji_build.py", line 98, in run_koji_build
    if results := self.create_srpm_if_needed():
  File "packit_service/worker/helpers/build/build_helper.py", line 517, in create_srpm_if_needed
    results = self._create_srpm()
  File "packit_service/worker/helpers/build/build_helper.py", line 568, in _create_srpm
    merged_ref = self._db_project_object.commit_sha