Wrong style of toctree caption due to breaking changes in docutils 0.17

[seisman]

Description of the problem

Go to https://www.pygmt.org/dev/, you will see:

The toctree captions don't show correctly, dut to breaking changes in docutils 0.17.

See related bug reports and possible fixes:

• broken alignment for captions in toctrees in ver. 0.5.1 readthedocs/sphinx_rtd_theme#1112
• toctree caption paragraphs miss the "caption" class readthedocs/sphinx_rtd_theme#1111
• should update CSS to reflect new docutils 0.17 HTML5 tags sphinx-doc/sphinx#9001
• CSS: support for aside.sidebar (from docutils 0.17+) sphinx-doc/sphinx#9059

I think we need to pin docutils to 0.16 as a workaround, and wait for upstream fixes. Agree?

[weiji14]

I think we need to pin docutils to 0.16 as a workaround, and wait for upstream fixes. Agree?

Since this only affects the dev doc page, I would wait for 24-48 hours to see if docutils does a bugfix release that would resolve things automatically.

[seisman]

More problems due to docutils 0.17:

[maxrjones]

All the lists are messed up as well: https://www.pygmt.org/dev/changes.html. Since there are so many problems, I think pinning to a prior version is appropriate rather than waiting.

[seisman]

Yes to me.

[maxrjones]

I think we can close this now, correct?