$ git clone -n https://src.fedoraproject.org/rpms/kde-gtk-config.git /var/lib/mock/f42-build-3279309-41337/root/chroot_tmpdir/scmroot/kde-gtk-config
Cloning into '/var/lib/mock/f42-build-3279309-41337/root/chroot_tmpdir/scmroot/kde-gtk-config'...
$ git fetch origin a53d2c57540ca969bcb21710637ede84d5b3d384:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kde-gtk-config
 * [new ref]         a53d2c57540ca969bcb21710637ede84d5b3d384 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a53d2c5 6.3.2