Follow-up from "Create components for highlighting vulnerability source code"

The following discussion from !158521 (merged) should be addressed:

• @jerasmus started a discussion:

  suggestion (non-blocking): since these are a set of plugins that are only used by the source viewer, I think we get rid of this function, and pass the plugins from the SourceViewer via the new registerPlugins function you've created below. Ideally anything in the highlight_js/ folder should remain independent and not require context from external components.

  I don't see it as a blocker for your MR, so feel free to open a follow-up for groupsource code to pick this up.