$ git clone -n https://src.fedoraproject.org/rpms/rubygem-childprocess.git /var/lib/mock/f42-build-3458038-45512/root/chroot_tmpdir/scmroot/rubygem-childprocess
Cloning into '/var/lib/mock/f42-build-3458038-45512/root/chroot_tmpdir/scmroot/rubygem-childprocess'...
$ git fetch origin 33e37a726c17c3089b5ec8cee704c44092794d58:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-childprocess
 * [new ref]         33e37a726c17c3089b5ec8cee704c44092794d58 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 33e37a7 Rebuilt for https://fedoraproject.org/wiki/Fedora_42_Mass_Rebuild