$ git clone -n https://src.fedoraproject.org/rpms/perl-Archive-Tar.git /var/lib/mock/f40-build-2212463-52268/root/chroot_tmpdir/scmroot/perl-Archive-Tar
Cloning into '/var/lib/mock/f40-build-2212463-52268/root/chroot_tmpdir/scmroot/perl-Archive-Tar'...
$ git fetch origin fe00007822cd196e424df95e136b07924178f790:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Archive-Tar
 * [new ref]         fe00007822cd196e424df95e136b07924178f790 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at fe00007 Update using of %%patch