$ git clone -n https://src.fedoraproject.org/rpms/rubygem-gem-nice-install.git /var/lib/mock/f45-build-34930-692/root/chroot_tmpdir/scmroot/rubygem-gem-nice-install
Cloning into '/var/lib/mock/f45-build-34930-692/root/chroot_tmpdir/scmroot/rubygem-gem-nice-install'...
$ git fetch origin f266585b106cea72487fb92c0bbbffc76bd5320a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-gem-nice-install
 * [new ref]         f266585b106cea72487fb92c0bbbffc76bd5320a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f266585 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild