Fix RichContentEditor usage
Fix RichContentEditor usage

On this particular branch, the RichContentEditor module
requires instantiation, whereas the current version's
public API is different and does not require instantiation.

Test Plan:
  - Follow the same plan as https://gerrit.instructure.com/76485

Change-Id: I22f9c4885bbc9fb8ba88ff4442a4f332759e42ad
Reviewed-on: https://gerrit.instructure.com/76849
Reviewed-by: Ethan Vizitei <73eeb0b2f65d05a906adf3b21ee1f9f5a2aa3c1c@instructure.com>
Product-Review: Clay Diffrient <9dff2e5c98626d20d2848250c411e8009465bb87@instructure.com>
Tested-by: Clay Diffrient <9dff2e5c98626d20d2848250c411e8009465bb87@instructure.com>
QA-Review: Clay Diffrient <9dff2e5c98626d20d2848250c411e8009465bb87@instructure.com>

venturehive/canvas-lms,roxolan/canvas-lms,grahamb/canvas-lms,grahamb/canvas-lms,grahamb/canvas-lms,sfu/canvas-lms,HotChalk/canvas-lms,sfu/canvas-lms,SwinburneOnline/canvas-lms,SwinburneOnline/canvas-lms,HotChalk/canvas-lms,HotChalk/canvas-lms,djbender/canvas-lms,djbender/canvas-lms,grahamb/canvas-lms,fronteerio/canvas-lms,venturehive/canvas-lms,roxolan/canvas-lms,sfu/canvas-lms,SwinburneOnline/canvas-lms,sfu/canvas-lms,HotChalk/canvas-lms,roxolan/canvas-lms,venturehive/canvas-lms,SwinburneOnline/canvas-lms,grahamb/canvas-lms,djbender/canvas-lms,venturehive/canvas-lms,fronteerio/canvas-lms,fronteerio/canvas-lms,roxolan/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,fronteerio/canvas-lms,djbender/canvas-lms,sfu/canvas-lms