add statsd capturing to ritex mml generation
add statsd capturing to ritex mml generation

fixes CNVS-29811

test plan:
- Create an assignment (or any content type with a body / description
  that uses RCS).
- Add a formula to the body / description.
- Observe that the formula is displayed.

Change-Id: I5c7ab3e1ba74c12654ac341983749122424ab6c4
Reviewed-on: https://gerrit.instructure.com/81691
Tested-by: Jenkins
Reviewed-by: Simon Williams <088e16a1019277b15d58faf0541e11910eb756f6@instructure.com>
QA-Review: Benjamin Christian Nelson <4a283f6b032925e40a485c88ede5597d7d65a090@instructure.com>
Product-Review: John Corrigan <3d73713d0cc718326e4fd7c06c64e067ad6e2270@instructure.com>

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