$ git clone -n https://src.fedoraproject.org/rpms/plasma-welcome.git /var/lib/mock/f40-build-2221908-52694/root/chroot_tmpdir/scmroot/plasma-welcome
Cloning into '/var/lib/mock/f40-build-2221908-52694/root/chroot_tmpdir/scmroot/plasma-welcome'...
$ git fetch origin 3b21d9f5dff8eb1fba8aa5c30bcf6d3cf31f6c9f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/plasma-welcome
 * [new ref]         3b21d9f5dff8eb1fba8aa5c30bcf6d3cf31f6c9f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3b21d9f 5.91.0