update docs styling

[janash]

Description

This PR updates styling on docs for the next branch of QCArchive.

I've made a sample build of my updates documentation on my fork. You can see it here: https://janash.github.io/QCFractal/index.html

Note - You might now need to add an additional parameter to your GHA for building the documentation. I've recently had to add

permissions: write-all

to use the deployment action in this workflow. See https://github.com/janash/QCFractal/blob/6ebb51a16519fa0a86fbabe0a21caedafb529899/.github/workflows/build_docs.yml#L11

The build docs workflow will fail without this addition (it has already on this PR)

Changelog description

• Colors changed to match QCA logo (in dark and light themes)
• Footer fixed updated to newer pydata sphinx format.
• Tabs/language labels added on all code blocks

Status

• Ready to go

[bennybp]

Looks great! Thanks