Design Management FE to FOSS Part 1/3: Move Design Management JS from EE to CE

What does this MR do?

This MR is part of the effort to move Design Management to FOSS (and Part 1/3 of the frontend component of this)

We:

• move all frontend code and tests for Design Management from EE to CE
• update all references to these files (i.e. fix imports)
  • importantly, in EE, we update the design management chunk import

Does this mean I can access Design Management in FOSS?

No (check by deleting EE directory and running gdk reconfigure && gdk restart) This MR does not mean Design Management is accessible in FOSS-only, even though all the relevant (frontend) code has been moved and will ship in FOSS; design management will only be available in FOSS once Item 3 from #212566 (closed) are resolved

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation (if required)
• [-] Code review guidelines
• [-] Merge request performance guidelines
• [-] Style guides
• [-] Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• [-] Tested in all supported browsers
• [-] Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• [-] Label as security and @ mention @gitlab-com/gl-security/appsec
• [-] The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• [-] Security reports checked/validated by a reviewer from the AppSec team