$ git clone -n https://src.fedoraproject.org/rpms/gnome-shell-extension-background-logo.git /var/lib/mock/f41-build-side-1-3128220-39561/root/chroot_tmpdir/scmroot/gnome-shell-extension-background-logo
Cloning into '/var/lib/mock/f41-build-side-1-3128220-39561/root/chroot_tmpdir/scmroot/gnome-shell-extension-background-logo'...
$ git fetch origin ed4fdb37972a74c2c517a2890230d3b98833631e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gnome-shell-extension-background-logo
 * [new ref]         ed4fdb37972a74c2c517a2890230d3b98833631e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ed4fdb3 Update to 47.0