Updates for doc theme

[dopplershift]

pydata-sphinx-theme released 0.5 with quite a few more configuration and customizable options. Some hightlights:

• Color variables
• Custom icons for links (rather than just github and twitter)--could add e.g. pypi
• Edit this page options
• Set pages to not have side bar
• Navbar alignment
• Header height

[dopplershift]

We can do this once the version chooser lands in a released version from upstream, at which point we'll be removing a bunch of our customization anyways.

[dopplershift]

At this time we should also update our Google Analytics setup since the current one will cease taking in data on 1 July 2023.

[dopplershift]

Might also consider looking at sphinx-design to handle our front page panels, since it's coming out the executable books project as well. We could avoid having to maintain HTML in index.rst.

[mgrover1]

@dopplershift is this something you or Drew has taken a look at? If not - I am planning on overhauling Py-ARTs sphinx docs too and could try to draft something later this week.

[dcamron]

I should be pushing our fixes up for 1.5 this morning! 👍

[mgrover1]

YAY! Very exciting!