Warning from numpydoc doesn't trigger Sphinx fail.

[MSeifert04]

The warning emitted in NumpyDocString isn't catched by sphinx so it passes the travis CI checks - though the section isn't even rendered in the output. I think these warnings should fail sphinx-builds.

A bit more information (not much) can be found in a recent PR to fix such a warning: astropy/astropy#4852

[astrofrog]

Can someone investigate this to see if it is still an issue?

[bsipocz]

This should have been fixed on the numpydoc side, at least we had tons of failures when they switched on failing on these warnings since 0.7?.
See e.g. numpy/numpydoc#115 and some of the v2.0.2 helpers update PRs.

(Please reopen if you think otherwise).