Resolve "Save changes on exam lab goes to edit lab or 500"

What does this mr do?

Whenever trying to edit an exam lab it would not allow it and just redirect to the edit page.

Actions taken to fix bug

Add a signOffIntervals field to be passed when editing a lab. Since exam lab depends on if it has sign-off intervals, it needs to be passed as a field for the update to check if it is possible.

Does this MR meet the acceptance criteria?

• I have added a changelog entry to reflect the significant changes I made and the bug I fixed.
• A test was created to test the bug.
• I have updated the documentation accordingly.
• I adhere to the style guide.

Closes #307 (closed)