$ git clone -n https://github.com/xcp-ng-rpms/xapi /var/lib/mock/v8.3-incoming-10532-29083/root/chroot_tmpdir/scmroot/xapi
Cloning into '/var/lib/mock/v8.3-incoming-10532-29083/root/chroot_tmpdir/scmroot/xapi'...
$ git fetch origin 80c1b0b81684762a73f80894e913cd4dedfa9d6c:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xapi
 * [new ref]         80c1b0b81684762a73f80894e913cd4dedfa9d6c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 80c1b0b Update to use upstream's 26.1.3-1 (#119)