$ git clone -n https://src.fedoraproject.org/rpms/im-chooser.git /var/lib/mock/f40-build-802335-143993/root/chroot_tmpdir/scmroot/im-chooser
Cloning into '/var/lib/mock/f40-build-802335-143993/root/chroot_tmpdir/scmroot/im-chooser'...
$ git fetch origin 03f0511a52a94886694414b7d2ea61ffb1e47cb9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/im-chooser
 * [new ref]         03f0511a52a94886694414b7d2ea61ffb1e47cb9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 03f0511 New upstream release.