Adds retry attempts to give pipeline status widget time to update

What does this MR do and why?

Describe in detail what your merge request does and why.

This adds retry attempts to give the pipeline status widget time to show that it has already passed.

Related: #340878 (closed)

MR acceptance checklist

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• I have evaluated the MR acceptance checklist for this MR.

qa/qa/specs/features/ee/browser_ui/4_verify/new_discussion_not_dropping_merge_trains_mr_spec.rb

@@ -53,9 +53,11 @@ module QA
         it 'does not drop MR', testcase: 'https://gitlab.com/gitlab-org/quality/testcases/-/quality/test_cases/1250' do
           start_discussion
 
-          Page::MergeRequest::Show.perform do |show|
-            show.has_pipeline_status?('passed')
-            expect(show).to be_merged
+          Support::Retrier.retry_until(max_attempts: 3, sleep_interval: 3) do
+            Page::MergeRequest::Show.perform do |show|
+              show.has_pipeline_status?('passed')
+              expect(show).to be_merged
+            end
           end
         end