[Registration] Custom fields - Cascade type is broken

[maieutiquer]

Q	A
Bug report?	yes
Version?	13.0.26

Steps:

1. Install Claroline from scratch
2. Login using an Admin account
3. Navigate to Administration -> Community -> Parameters
4. Check the "Enable self-registration" checkbox and Save
5. Navigate to Administration -> Community -> User Profile
6. Create a new "section" and add a new "field" of type "Choice"
7. Type something in the Name field and under Parameters add some choices in the Choices list

8. Click Save on the modal and then click Save on the bottom toolbar

9. (optional) If this does not work, try removing the Choice type, then adding a Text type, then adding a Choice and removing the Text

Expected: the Registration form should be as designed in the Administration

Actual: the registration form does not display Choice options (even after deleting the section and retrying in a new Section, same error appears)