MDL-42097 formslib: updates to edit profile form

Add a new dependency 'on' in forms library
Use the 'in' dependency to disable the 'changepassword' field when a auth plugin doesn't support it
MDL-42097 auth: Auth plugins must check passwordurl before returning it
MDL-42097 behat: Add behat tests
MDL-43010 behat: Add steps expand/collapse in the