Fix docutils deprecated set_class method

[nikola-matic]

def set_class(self, name):
    """Add a new class to the "classes" attribute."""
    warnings.warn('docutils.nodes.Element.set_class() is deprecated; '
                  ' and will be removed in Docutils 0.21 or later.'
                  "Append to Element['classes'] list attribute directly",
                  DeprecationWarning, stacklevel=2)
    assert ' ' not in name
    self['classes'].append(name.lower())

Didn't find a mention of the deprecation in their docs, so dug it out in code. Also, the spinx-build output is pretty useless, so for future reference, add a -T option for more verbose output when necessary.

[r0qs]

def set_class(self, name):
    """Add a new class to the "classes" attribute."""
    warnings.warn('docutils.nodes.Element.set_class() is deprecated; '
                  ' and will be removed in Docutils 0.21 or later.'
                  "Append to Element['classes'] list attribute directly",
                  DeprecationWarning, stacklevel=2)
    assert ' ' not in name
    self['classes'].append(name.lower())

Didn't find a mention of the deprecation in their docs, so dug it out in code. Also, the spinx-build output is pretty useless, so for future reference, add a -T option for more verbose output when necessary.

This is the only thing I found about it in their repo: https://sourceforge.net/p/docutils/bugs/463/. I'm wondering how did you run in a issue with the current version.

[r0qs]

Oh, just saw it now in my own PR: https://app.circleci.com/pipelines/github/ethereum/solidity/31879/workflows/a62569ae-b31f-42a1-b527-c47bcc4a3eee/jobs/1424075/parallel-runs/0/steps/0-103 haha

[cameel]

I see in the rendered docs that the right classes still get added with this change so it's good.