$ git clone -n https://src.fedoraproject.org/rpms/plasma-wallpapers-dynamic.git /var/lib/mock/f40-build-788678-135301/root/chroot_tmpdir/scmroot/plasma-wallpapers-dynamic
Cloning into '/var/lib/mock/f40-build-788678-135301/root/chroot_tmpdir/scmroot/plasma-wallpapers-dynamic'...
$ git fetch origin 647a6bb8b13178dbfa678f29354c2e81ff7fe2f6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/plasma-wallpapers-dynamic
 * [new ref]         647a6bb8b13178dbfa678f29354c2e81ff7fe2f6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 647a6bb Rebuilt for libavif 1.0.3