Courses: Infinite loading/console error on adding question to existing test step

[jsschf]

Steps to reproduce

• Choose any course with tests
• Edit the course
• Click on one of the steps with a test
• Click "Update Test"
• Add a question of any kind
• Click "Save & Return"
• Click "Submit"

Here's a screen recording:
https://www.loom.com/share/6bfe51c8bbb843819f35cae5ca9445af

Here's the console error:

[jsschf]

This also works if you click "Update Test" and then hit "Save & Return" without adding any questions

[jsschf]

Once you reach the infinite loading and get the max call stack size console error, if you hit back in the browser, then hit "Save and Return" again, you get the following console errror:

Here is an updated Loom:
https://www.loom.com/share/c2931549c4ed425aa94a83266c7fb061