Before this commit, XBlock static assets were extracted during the
collectstatic process by iterating through all installed XBlock classes
and creating a separate directory for each. However, some packages
install many XBlocks that actually share the same static assets. The
most notable example is problem_builder, though we also see this with
schoolyourself and google_drive.

This commit uses the parent module name to do package asset lookup,
collapsing those cases down and eliminating duplicates. For a default
install of edx-platform XBlocks, this reduces assets generated from 31M
to 14M.

Includes:
* CAPA
* ORA
* LTI
* LTI-Consumer
* SGA
* Randomized Content Block

TNL-5692
TNL-5464

This reverts commit 9aa35cd8.

This reverts commit 0ea8e1b9, reversing
changes made to e3db08f1.

Potential Grades revert PR

This reverts commit c050ccc3, reversing
changes made to 9ba97722.