$ git clone -n https://src.fedoraproject.org/rpms/txt2rss.git /var/lib/mock/f41-build-1042170-18998/root/chroot_tmpdir/scmroot/txt2rss
Cloning into '/var/lib/mock/f41-build-1042170-18998/root/chroot_tmpdir/scmroot/txt2rss'...
$ git fetch origin c02568787ae0172f0f9b840111a3170b4ff93300:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/txt2rss
 * [new ref]         c02568787ae0172f0f9b840111a3170b4ff93300 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c025687 Eliminate use of obsolete %patchN syntax (#2283636)