Add myst-parser to sphinx docker images
Problem to solve
Currently sphinx images only include recommonmark package. That package is already deprecated and should be replaced with myst-parser
package:
- https://github.com/readthedocs/recommonmark
- https://www.sphinx-doc.org/en/master/usage/markdown.html
Further details
Looks like it is safe to have both packages. The extension is explicitly loaded in the conf.py, so the project can decide which extension to use.
Proposal
Add myst-parser
package to the docker images.