$ git clone -n https://src.fedoraproject.org/rpms/ansible-core.git /var/lib/mock/f42-build-side-1-3568041-46743/root/chroot_tmpdir/scmroot/ansible-core
Cloning into '/var/lib/mock/f42-build-side-1-3568041-46743/root/chroot_tmpdir/scmroot/ansible-core'...
$ git fetch origin 2140cacf0d22f25fdc1a49b0ab7cf062a7d482b8:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ansible-core
 * [new ref]         2140cacf0d22f25fdc1a49b0ab7cf062a7d482b8 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2140cac Update to 2.18.6. Fixes rhbz#2354908.