Return bad request from pipelines controller for invalid ci yaml

Change response from ok

app/controllers/projects/pipelines_controller.rb

@@ -60,10 +60,10 @@ class Projects::PipelinesController < Projects::ApplicationController
       .new(project, current_user, create_params)
       .execute(:web, ignore_skip_ci: true, save_on_errors: false)
 
-    if @pipeline.persisted?
+    if @pipeline.created_successfully?
       redirect_to project_pipeline_path(project, @pipeline)
     else
-      render 'new'
+      render 'new', status: :bad_request
     end
   end
 

spec/controllers/projects/pipelines_controller_spec.rb

@@ -634,7 +634,8 @@ describe Projects::PipelinesController do
       it 'does not persist a pipeline' do
         expect { post_request }.not_to change { project.ci_pipelines.count }
 
-        expect(response).to have_gitlab_http_status(:ok)
+        expect(response).to have_gitlab_http_status(:bad_request)
+        expect(response).to render_template('new')
       end
     end