py-myst-parser: test phase fails because of missing dependencies

[reneeotten (Renee Otten)]

The test phase fails because of missing dependencies, upstream lists

testing = [
    "beautifulsoup4",
    "coverage[toml]",
    "pytest>=7,<8",
    "pytest-cov",
    "pytest-regressions",
    "pytest-param-files~=0.3.4",
    "sphinx-pytest",

the last two are not listed in the Portfile nor are currently present in MacPorts. The ones related to coverage are likely not needed as we run pytest with -o addopts= which usually turns off the coverage tests.

If you decide to keep the test phase and add the missing dependencies, it can likely be simplified as test.run will automatically set-up the correct variables in the python PG for using pytest in the test-phase.

[reneeotten (Renee Otten)]

In e6b31ad089766dbc7dcfc9270ca5816162aa5feb/macports-ports (master):

py-myst-parser: fix test phase, drop py37 subport

Closes: #68231