CoursesAdd: Errors with step descriptions

[paulbert]

If you have a course with one step with a description, add a step and just click Return to List then click back and forth the description will eventually always show the text for the first step or blank no matter what step you are looking at.

May be related to #6833, so I'm going to put this On Hold until we've investigated that one more.

https://www.loom.com/share/42c7472992e74d1d8232780fca226936