Fixed issue boards closed list not listing all issues

This was a regression caused by the backlog list being re-added

Closes #33850

app/services/boards/issues/list_service.rb

@@ -3,7 +3,7 @@ module Boards
     class ListService < BaseService
       def execute
         issues = IssuesFinder.new(current_user, filter_params).execute
-        issues = without_board_labels(issues) unless movable_list?
+        issues = without_board_labels(issues) unless movable_list? || closed_list?
         issues = with_list_label(issues) if movable_list?
         issues.order_by_position_and_priority
       end
@@ -21,7 +21,15 @@ module Boards
       end
 
       def movable_list?
-        @movable_list ||= list.present? && list.movable?
+        return @movable_list if defined?(@movable_list)
+
+        @movable_list = list.present? && list.movable?
+      end
+
+      def closed_list?
+        return @closed_list if defined?(@closed_list)
+
+        @closed_list = list.present? && list.closed?
       end
 
       def filter_params

changelogs/unreleased/issue-boards-closed-list-all.yml

+---
+title: Fixed issue boards closed list not showing all closed issues
+merge_request:
+author:

spec/services/boards/issues/list_service_spec.rb

@@ -67,7 +67,7 @@ describe Boards::Issues::ListService, services: true do
 
         issues = described_class.new(project, user, params).execute
 
-        expect(issues).to eq [closed_issue4, closed_issue2, closed_issue3, closed_issue1]
+        expect(issues).to eq [closed_issue4, closed_issue2, closed_issue5, closed_issue3, closed_issue1]
       end
 
       it 'returns opened issues that have label list applied when listing issues from a label list' do