Reapply warning suppression at the website building level

[droumis]

No description provided.

[maximlt]

nbsite has a feature that allows to inject some startup code that is executed before running the cells of a notebook evaluated with the NotebookDirective. It even ships with a default startup file that ignores all warnings.

import warnings

warnings.filterwarnings("ignore")

import matplotlib as mpl

mpl.use('agg')

try:
    import holoviews.plotting.bokeh  # noqa
except Exception:
    pass

try:
    import holoviews.plotting.mpl as hmpl
    hmpl.MPLPlot.fig_alpha = 0
except Exception:
    pass

There are now some HoloViz websites (param, hvplot, examples) whose notebook (and MyST Markdown) pages are no longer built with nbsite and its NotebookDirective but directly with sphinx and https://github.com/executablebooks/MyST-NB. As far as I can see, they do not offer this startup configuration feature that nbsite has. We need to find a way to enable that, opening an issue on MyST-NB (or wherever it's relevant) would make sense too.

[hoxbro]

We could, for our CI, maybe set the following environment variable: PYTHONWARNINGS="ignore"

[maximlt]

We could, for our CI, maybe set the following environment variable: PYTHONWARNINGS="ignore"

This works but is also a bigger hammer since it not only ignores the warnings emitted when running the code/notebook but also those potentially emitted by the doc build toolchain (sphinx, pydata-sphinx-theme, etc.).