Describe the bug
When editing a notebook gradeable with the notebook builder, adding a markdown textbox results in the textbox being only 1 character wide and not expandable horizontally

Expected behavior
The markdown box should be large enough to comfortably type in and resizable if the content stretches past the boundaries of the box

To Reproduce
Steps to reproduce the behavior:

1. Create a new gradeable
2. Fill in the requirement information
3. Click that some of this assignment will be manually graded
4. Click no for the rest of the options
5. Go to the submissions/autograding tab
6. Click start new under the notebook builder section
7. Add a markdown component
8. See error

Configuration

• OS: [e.g. Windows, Linux, ...]
• Browser [e.g. Chrome, Safari]

Screenshots

Additional context
Could be related to #11916