Replace node-sass with sass

What does this MR do?

The node-sass project is deprecated in favor of sass, written in dart. Apparently node-sass doesn't compile for node@16, erroring out for community contributors and team members alike. It seems like there is not a quick fix available for this:

https://github.com/sass/node-sass/issues/3077

Given that the project is deprecated and we do not really use it for anything time sensitive, we can surely just replace node-sass with sass.

Does this MR meet the acceptance criteria?

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