fix review creation

app/models/review.rb

@@ -27,7 +27,7 @@ class Review < ApplicationRecord
   has_many :rates
   has_many :complaints, as: :complaintable
 
-  validates_presence_of :user, :reviewable, :review_ratings
+  validates_presence_of :user, :reviewable
   validates_inclusion_of :reviewable_type, in: %w(LearningObject Collection), message: 'Only LearningObjects and Collections are reviewable.'
   validates_uniqueness_of :user, scope: [:reviewable_id, :reviewable_type]