$ git clone -n https://src.fedoraproject.org/rpms/qt5-qt3d.git /var/lib/mock/f39-build-1762411-41498/root/chroot_tmpdir/scmroot/qt5-qt3d
Cloning into '/var/lib/mock/f39-build-1762411-41498/root/chroot_tmpdir/scmroot/qt5-qt3d'...
$ git fetch origin 208c1f4e54fbf0edbdeb9e91e89fda5e3d36c496:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/qt5-qt3d
 * [new ref]         208c1f4e54fbf0edbdeb9e91e89fda5e3d36c496 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 208c1f4 Update sources