$ git clone -n https://src.fedoraproject.org/rpms/jakarta-saaj.git /var/lib/mock/f40-build-2715634-72496/root/chroot_tmpdir/scmroot/jakarta-saaj
Cloning into '/var/lib/mock/f40-build-2715634-72496/root/chroot_tmpdir/scmroot/jakarta-saaj'...
$ git fetch origin 72551f7e0cbe40e8f229e2a3cd8d376bb6a29fb5:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/jakarta-saaj
 * [new ref]         72551f7e0cbe40e8f229e2a3cd8d376bb6a29fb5 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 72551f7 Rebuilt for java-21-openjdk as system jdk