Restore check for completed pipelines for stages

app/models/ci/pipeline.rb

@@ -401,6 +401,11 @@ module Ci
         # The `Ci::Stage` contains all up-to date data
         # as atomic processing updates all data in-bulk
         stages
+      elsif complete?
+        # The `Ci::Stage` contains up-to date data only for `completed` pipelines
+        # this is due to asynchronous processing of pipeline, and stages possibly
+        # not updated inline with processing of pipeline
+        stages
       else
         # In other cases, we need to calculate stages dynamically
         legacy_stages