$ git clone -n https://src.fedoraproject.org/rpms/plasma-mobile.git /var/lib/mock/f41-build-824542-154178/root/chroot_tmpdir/scmroot/plasma-mobile
Cloning into '/var/lib/mock/f41-build-824542-154178/root/chroot_tmpdir/scmroot/plasma-mobile'...
$ git fetch origin 4b275c566ef6157c373f797af094f44a2e8a22f6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/plasma-mobile
 * [new ref]         4b275c566ef6157c373f797af094f44a2e8a22f6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4b275c5 rebuild