Optimize SCSS Build Pipeline

[schreiaj]

Currently our SCSS builds happen on first load and take a non-trivial amount of time. This is due to how we are importing USWDS which is an approach they recommend against

Removing this line and adding only the packages we use does significantly improve compilation times however hunting down all the packages we use and testing each page requires a bit of effort.

[bora-skylight]

@schreiaj @zdeveloper adding this to the sprint, correct?

[schreiaj]

It's not a blocker, but the sooner we resolve it likely the less effort it will be.