$ git clone -n https://src.fedoraproject.org/rpms/perl-File-MMagic-XS.git /var/lib/mock/f41-build-815848-149783/root/chroot_tmpdir/scmroot/perl-File-MMagic-XS
Cloning into '/var/lib/mock/f41-build-815848-149783/root/chroot_tmpdir/scmroot/perl-File-MMagic-XS'...
$ git fetch origin 3ed35b2a1dbae91e943613c7295fdd350bec2272:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-File-MMagic-XS
 * [new ref]         3ed35b2a1dbae91e943613c7295fdd350bec2272 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3ed35b2 Perl 5.40 rebuild