Fix gitlab ci widget for forks

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

app/controllers/projects/merge_requests_controller.rb

@@ -166,7 +166,7 @@ class Projects::MergeRequestsController < Projects::ApplicationController
   end
 
   def ci_status
-    status = project.gitlab_ci_service.commit_status(merge_request.last_commit.sha)
+    status = @merge_request.source_project.gitlab_ci_service.commit_status(merge_request.last_commit.sha)
     response = {status: status}
 
     render json: response