Enable SAST spec performance improvement

Improve the performance of the
Enable SAST end to end spec by
merging the test MR immediately
rather than waiting on the MR
pipeline to succeed

qa/qa/page/merge_request/show.rb

@@ -287,6 +287,17 @@ module QA
           raise "Rebase did not appear to be successful" unless success
         end
 
+        def merge_immediately!
+          merge_moment_dropdown_found = has_element?(:merge_moment_dropdown, wait: 0)
+
+          if merge_moment_dropdown_found
+            click_element(:merge_moment_dropdown)
+            click_element(:merge_immediately_menu_item)
+          else
+            click_element(:merge_button)
+          end
+        end
+
         def try_to_merge!
           # Revisit after merge page re-architect is done https://gitlab.com/gitlab-org/gitlab/-/issues/300042
           # To remove page refresh logic if possible

qa/qa/specs/features/ee/browser_ui/secure/enable_sast_from_configuration_spec.rb

@@ -120,7 +120,7 @@ module QA
         end
 
         Page::MergeRequest::Show.perform do |merge_request|
-          merge_request.try_to_merge!
+          merge_request.merge_immediately!
         end
 
         Flow::Pipeline.visit_latest_pipeline