Use flash.now for VSA notice

ee/app/controllers/groups/analytics/cycle_analytics_controller.rb

@@ -22,7 +22,7 @@ class Groups::Analytics::CycleAnalyticsController < Groups::Analytics::Applicati
 
   def show
     epic_link_start = '<a href="%{url}" target="_blank" rel="noopener noreferrer">'.html_safe % { url: "https://gitlab.com/groups/gitlab-org/-/epics/6046" }
-    flash[:notice] = s_("ValueStreamAnalytics|Items in Value Stream Analytics are currently filtered by their creation time. There is an %{epic_link_start}epic%{epic_link_end} that will change the Value Stream Analytics date filter to use the end event time for the selected stage.").html_safe % { epic_link_start: epic_link_start, epic_link_end: "</a>".html_safe }
+    flash.now[:notice] = s_("ValueStreamAnalytics|Items in Value Stream Analytics are currently filtered by their creation time. There is an %{epic_link_start}epic%{epic_link_end} that will change the Value Stream Analytics date filter to use the end event time for the selected stage.").html_safe % { epic_link_start: epic_link_start, epic_link_end: "</a>".html_safe }
   end
 
   private