Drop the static path configuration for the Sphinx docs

There are no static files at this time. I don't know the first thing about CSS and rely on my elders and betters to make the documentation look presentable. Configuring a static directory also generates a Sphinx warning when it isn't present (which it isn't on clean checkouts because it's empty) so just remove it.

Signed-off-by: Jeremy Cline jcline@redhat.com