Add delete review test

spec/acceptance/reviews_spec.rb

 require 'acceptance_helpers'
+require 'shared/contexts'
 
 resource 'Reviews' do
   header 'Accept', 'application/json'
@@ -7,6 +8,7 @@ resource 'Reviews' do
   before { 12.times { create(:learning_object) } }
 
   let(:learning_objects) { LearningObject.all }
+  let(:reviews) { Review.all }
 
   get '/v1/:type/:id/reviews' do
     parameter :type, 'type of object [\'learning_objects\', \'collections\']'
@@ -20,5 +22,26 @@ resource 'Reviews' do
       expect(status).to eq(200)
     end
   end
+  
+  delete '/v1/:type/:id/reviews/:review_id' do
+    include_context 'authenticate_user'
+
+    parameter :id, 'The id of object'
+    parameter :type, 'type of object [\'learning_objects\', \'collections\']'
+    parameter :review_id, 'The id of review'
+
+    before do
+      @review = create(:review, user: @user, reviewable: learning_objects.first)
+    end
+
+    let(:type) { 'learning_objects' }
+    let(:id) { learning_objects.first.id }
+    let(:review_id) { @review.id }
+
+    example_request 'Delete a review' do
+      expect(path).to eq("/v1/learning_objects/#{id}/reviews/#{review_id}") # `:id` is replaced with the value of `id`
+      expect(status).to eq(200)
+    end
+  end
 
 end