$ git clone -n https://src.fedoraproject.org/rpms/libmatroska.git /var/lib/mock/f40-build-785609-134039/root/chroot_tmpdir/scmroot/libmatroska
Cloning into '/var/lib/mock/f40-build-785609-134039/root/chroot_tmpdir/scmroot/libmatroska'...
$ git fetch origin 52efd60fbfde6515808eb2573c4aeeb98dc9e5bd:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libmatroska
 * [new ref]         52efd60fbfde6515808eb2573c4aeeb98dc9e5bd -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 52efd60 Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild