$ git clone -n https://src.fedoraproject.org/rpms/jpegxl.git /var/lib/mock/f45-build-43641-804/root/chroot_tmpdir/scmroot/jpegxl
Cloning into '/var/lib/mock/f45-build-43641-804/root/chroot_tmpdir/scmroot/jpegxl'...
$ git fetch origin c3b9163ecab9b3d0c629b2e8523ff795c3b7b35f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/jpegxl
 * [new ref]         c3b9163ecab9b3d0c629b2e8523ff795c3b7b35f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c3b9163 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild