Sphinx throws warnings on two of existing spec files:
> cinder-specs/doc/source/specs/liberty/clone-image-in-glance-cinder-backend.rst:173:
WARNING: Footnote [2] is not referenced.
> cinder-specs/doc/source/specs/newton/discovering-system-capabilities.rst:356:
WARNING: Footnote [4] is not referenced.
These need to be fixed before we can switch to new way of building specs
as recomended by OpenStack Project Testing Interface:
https://governance.openstack.org/tc/reference/project-testing-interface.html#documentation
Change-Id: Ibe58c27303f49a72779f0d5ebdd52c001ee8b23c
Closes-Bug: 1810677