$ git clone -n https://github.com/xcp-ng-rpms/qemu.git /var/lib/mock/v8.3-incoming-9813-28523/root/chroot_tmpdir/scmroot/qemu
Cloning into '/var/lib/mock/v8.3-incoming-9813-28523/root/chroot_tmpdir/scmroot/qemu'...
$ git fetch origin 6da05c99019eb437a857a7568a0b28bc064b905c:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/qemu
 * [new ref]         6da05c99019eb437a857a7568a0b28bc064b905c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6da05c9 Merge remote-tracking branch 'origin/XS-8.3'