$ git clone -n https://src.fedoraproject.org/rpms/perl-Time-OlsonTZ-Download.git /var/lib/mock/f45-build-27159-621/root/chroot_tmpdir/scmroot/perl-Time-OlsonTZ-Download
Cloning into '/var/lib/mock/f45-build-27159-621/root/chroot_tmpdir/scmroot/perl-Time-OlsonTZ-Download'...
$ git fetch origin fa2736b8f014321bfd23902e75a7f1279785bd6f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Time-OlsonTZ-Download
 * [new ref]         fa2736b8f014321bfd23902e75a7f1279785bd6f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at fa2736b Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild