Questions in "Review & Edit" and "Generate Questions" tabs are inconsistent

[kathleentom]

Steps to reproduce

1. Generate a specific number of questions, then go to Review & Edit.
2. Modify the number of questions, either by deleting question(s) or adding question(s).
3. Go back to Generate Questions > Back to AI Plan Configuration.
4. Observe that the questions in the Question Plan are still the original questions, and they have not been modified.
5. Additionally, in navbar on the left, observe that the number of questions has not been updated. For eg, after deleting 4 questions from this quiz, it should say 1 question instead of 5: