$ git clone -n https://src.fedoraproject.org/rpms/relaxng-datatype-java.git /var/lib/mock/f40-build-2487156-61650/root/chroot_tmpdir/scmroot/relaxng-datatype-java
Cloning into '/var/lib/mock/f40-build-2487156-61650/root/chroot_tmpdir/scmroot/relaxng-datatype-java'...
$ git fetch origin bf71913f6f6ee5f4d3daf8684c5b28d49b9a196c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/relaxng-datatype-java
 * [new ref]         bf71913f6f6ee5f4d3daf8684c5b28d49b9a196c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at bf71913 bump of release for for java-21-openjdk as system jdk