$ git clone -n https://src.fedoraproject.org/rpms/mctc-lib.git /var/lib/mock/f41-build-832427-14888/root/chroot_tmpdir/scmroot/mctc-lib
Cloning into '/var/lib/mock/f41-build-832427-14888/root/chroot_tmpdir/scmroot/mctc-lib'...
$ git fetch origin 68c29cd7f9c23a628dd493bbf1ceceaf89aa5a36:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mctc-lib
 * [new ref]         68c29cd7f9c23a628dd493bbf1ceceaf89aa5a36 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 68c29cd Eliminate use of obsolete %patchN syntax (#2283636)