* Update sass-loader@16.0.2
* Update sass part 1 (actually update it)
* Update scss files to remove at-charset and use at-use instead of at-import
at-charset hasn't been needed since we switched to dart-sass, and
at-import is now deprecated. Most of this was done using sass-migrator.
We still use at-import for files imported from node_modules, but sass
doesn't seem to complain about that
* Inline at-extend rule that was causing an error
* Remove or inline at-use rules in components package
c519bee236