$ git clone -n https://src.fedoraproject.org/rpms/perl-YAML-LibYAML.git /var/lib/mock/f40-build-778609-130011/root/chroot_tmpdir/scmroot/perl-YAML-LibYAML
Cloning into '/var/lib/mock/f40-build-778609-130011/root/chroot_tmpdir/scmroot/perl-YAML-LibYAML'...
$ git fetch origin fba5dbf9bf68edb8f5b2c1349c15313ea0bd0c03:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-YAML-LibYAML
 * [new ref]         fba5dbf9bf68edb8f5b2c1349c15313ea0bd0c03 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at fba5dbf Break a build cycle: perl-YAML-LibYAML → perl-boolean → perl-JSON-MaybeXS → perl-Cpanel-JSON-XS → perl-YAML-LibYAML