1. Core > User/Access > Profile > Manage Roles.
  2. I clicked on the Content Editor role. 
  3. On the left, click on Tasks
  4. Then,click Edit in the top-right.
  5. Uncheck all boxes for these tasks:
    • Manage Forms Category
    • Add Form Item
    • Edit Forms
  6. Save & Exit.
Note: When you add or remove tasks for a role, the members of that role must sign out and sign in again before they see the results of those changes.