I want to get rid of UserWarning seen in astropy/astropy#7928 and I think I can do it as long as I can figure out where to put this text_file_format = 'rst' option. Is it in setup.cfg or conf.py? Which section? Do I need quotes ('rst' vs rst) in the setting?

https://github.com/astropy/pytest-doctestplus/blob/720266fcc37e878c25f8b832ff10677dabacaad7/pytest_doctestplus/plugin.py#L206-L214