$ git clone -n https://src.fedoraproject.org/rpms/man-db.git /var/lib/mock/f39-build-1621444-38721/root/chroot_tmpdir/scmroot/man-db
Cloning into '/var/lib/mock/f39-build-1621444-38721/root/chroot_tmpdir/scmroot/man-db'...
$ git fetch origin 4de9a52cd338b5e4b62e4574f8d1c6cc9f3e8780:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/man-db
 * [new ref]         4de9a52cd338b5e4b62e4574f8d1c6cc9f3e8780 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4de9a52 Release bump after added Patch0 from yselkowitz