$ git clone -n https://src.fedoraproject.org/rpms/rubygem-hashdiff.git /var/lib/mock/f39-build-1458386-33054/root/chroot_tmpdir/scmroot/rubygem-hashdiff
Cloning into '/var/lib/mock/f39-build-1458386-33054/root/chroot_tmpdir/scmroot/rubygem-hashdiff'...
$ git fetch origin 283e90ac4b7e29e6801b5d3abfc0c9df81193818:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-hashdiff
 * [new ref]         283e90ac4b7e29e6801b5d3abfc0c9df81193818 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 283e90a Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild