$ git clone -n https://src.fedoraproject.org/rpms/migrate.git /var/lib/mock/f41-build-854302-166838/root/chroot_tmpdir/scmroot/migrate
Cloning into '/var/lib/mock/f41-build-854302-166838/root/chroot_tmpdir/scmroot/migrate'...
$ git fetch origin 357fada6ba8a7318e9e3bb4e18a9c54e60c3d19e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/migrate
 * [new ref]         357fada6ba8a7318e9e3bb4e18a9c54e60c3d19e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 357fada Fix FTBFS on F41 (RHBZ#2300942)