$ git clone -n https://src.fedoraproject.org/rpms/wingpanel.git /var/lib/mock/f42-build-side-1-3555801-46656/root/chroot_tmpdir/scmroot/wingpanel
Cloning into '/var/lib/mock/f42-build-side-1-3555801-46656/root/chroot_tmpdir/scmroot/wingpanel'...
$ git fetch origin 173cb8c5131663473b3e89f4bcf74f5f4c6b1225:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/wingpanel
 * [new ref]         173cb8c5131663473b3e89f4bcf74f5f4c6b1225 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 173cb8c Bump to commit 7990904 for compatibility with mutter 48