PF4 component source maps

[Hyperkid123]

Source maps are not generated per component basis, only for the index.js. If you use absolute import paths, the console in the browser will be swarmed with warnings:

Solution: generate source maps for all components.

[rachael-phillips]

Thanks for opening this! cc @evwilkin

[evwilkin]

@Hyperkid123 FYI we've pulled this into the current milestone - it will be incorporated in the work @redallen is doing towards #3972 , which is currently breaking down #4010 into smaller PRs for review.