$ git clone -n https://src.fedoraproject.org/rpms/feather.git /var/lib/mock/f41-build-852569-166403/root/chroot_tmpdir/scmroot/feather
Cloning into '/var/lib/mock/f41-build-852569-166403/root/chroot_tmpdir/scmroot/feather'...
$ git fetch origin c4086d1dcad1629747aa67844e28e6dd3c057f70:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/feather
 * [new ref]         c4086d1dcad1629747aa67844e28e6dd3c057f70 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c4086d1 Fix build on f41