$ git clone -n https://src.fedoraproject.org/rpms/spamassassin.git /var/lib/mock/f40-build-2260892-54424/root/chroot_tmpdir/scmroot/spamassassin
Cloning into '/var/lib/mock/f40-build-2260892-54424/root/chroot_tmpdir/scmroot/spamassassin'...
$ git fetch origin 78f14cdc7ace242a955341b8831faad8d636ec8b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/spamassassin
 * [new ref]         78f14cdc7ace242a955341b8831faad8d636ec8b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 78f14cd Bring back still needed part of configure C compatibility fix