Implement design system inputs

Part of https://github.com/conda-incubator/conda-store-ui/issues/288

Description

This pull request:

Implements the inputs of the design system

Default

Hover

Focus

Pull request checklist

[x] Did you test this change locally?
[x] Did you update the documentation (if required)?
[x] Did you add/update relevant tests for this change (if required)?

Additional information

Implemented the first version of the inputs using green for focus

I had to implement the first version of the inputs system that was using the primary color as the focus color because all the components in MUI use either the primary, secondary, warn, info or success colors. The accent color is something we added to the palette but it is not formally defined in the MUI API which means that it will not override by default.

I tried to stick to use the accent color and it was mainly working at first, but later I started to see that there were some other component's focus that were changing as a result of trying to override it,