$ git clone -n https://src.fedoraproject.org/rpms/jack-audio-connection-kit.git /var/lib/mock/f40-build-2004929-45012/root/chroot_tmpdir/scmroot/jack-audio-connection-kit
Cloning into '/var/lib/mock/f40-build-2004929-45012/root/chroot_tmpdir/scmroot/jack-audio-connection-kit'...
$ git fetch origin ca9e61d2bbf44608b63e1d010dca4a7f8ab0626b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/jack-audio-connection-kit
 * [new ref]         ca9e61d2bbf44608b63e1d010dca4a7f8ab0626b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ca9e61d fix build against newer Python