$ git clone -n https://src.fedoraproject.org/rpms/cosmic-player.git /var/lib/mock/f42-flatpak-app-build-59152440-6571325/root/chroot_tmpdir/scmroot/cosmic-player
Cloning into '/var/lib/mock/f42-flatpak-app-build-59152440-6571325/root/chroot_tmpdir/scmroot/cosmic-player'...
$ git fetch origin 33c8dcb78f1168ef13fec2f3d0dcfa9de8c63a48:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/cosmic-player
 * [new ref]         33c8dcb78f1168ef13fec2f3d0dcfa9de8c63a48 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 33c8dcb "Update to 1.0.0~alpha.7"