a11y-high-contrast-light errors showing up in Sphinx on main

[choldgraf]

I am trying to get some improvements into the sphinx-book-theme using main from this theme, and finding this error message that keeps popping up:

E         + WARNING: Color theme a11y-high-contrast-light not found by pygments, falling back to tango.
E         + WARNING: Color theme a11y-high-contrast-dark not found by pygments, falling back to monokai.

Any idea why this would be happening? cc @drammock who authored the PR where I believe these were added:

• ENH: Accessible code highlighting styles #1064

[choldgraf]

Ah I think this is because we only installed the accessible-pygments package in our doc environment, it's not a dependency:

https://github.com/pydata/pydata-sphinx-theme/pull/1064/files#diff-50c86b7ed8ac2cf95bd48334961bf0530cdc77b5a56f852c5c61b89d735fd711R54

My feeling is that we want the default install to not build with any warnings, so we should either make accessible-pygments a dependency of the theme, or we should remove the warning and default to not using accessible-pygments.

[drammock]

oops. yeah, I think you've diagnosed correctly. I should have added it as a full dependency, not just for doc.

[drammock]

i'll open a quick PR