Replace moment.js

moment is now in maintenance mode. We should consider porting to an active library.

https://momentjs.com/docs/

This will also cut down on the unneeded bloat in main.min.js that we have to manually discard every time we run `npm run webpack`

If we want to address this without removing moment entirely, we can look into using the following plugin to cut down on main.min.js bloat: https://www.npmjs.com/package/moment-locales-webpack-plugin