ADD a "Save all" button in the add question page

**Is your feature request related to a problem? Please describe.**
As a TA, I would like to have a "save all" button, so I don't need to go through each question and click save one by one.

**Describe the solution you'd like**
Add a button that saves all the questions.

**Describe alternatives you've considered**
N/A

**Additional context**
N/A