Added codeowner section names to merge request edit form

Closes https://gitlab.com/gitlab-org/gitlab/-/issues/227136

changelogs/unreleased/ph-227136-codeOwnersSectionNameMRForm.yml

+---
+title: Added section names to code owner approvals in merge request form
+merge_request:
+author:
+type: added

ee/app/views/projects/merge_requests/_code_owner_approval_rules.html.haml

@@ -17,7 +17,10 @@
       %tbody{ data: { qa_selector: "approver_list" } }
         - code_owner_rules.each do |code_owner_approval_rule|
           %tr{ data: { qa_selector: "approver" } }
-            %td.monospace= code_owner_approval_rule.name
+            %td
+              - if code_owner_approval_rule.section != Gitlab::CodeOwners::Entry::DEFAULT_SECTION
+                %span.text-muted.small.d-block= code_owner_approval_rule.section
+              %span.monospace= code_owner_approval_rule.name
             %td.d-none.d-sm-table-cell
               - code_owner_approval_rule.approvers.each do |approver|
                 = user_avatar(user: approver)

ee/spec/features/projects/merge_requests/user_edits_merge_request_spec.rb

@@ -18,7 +18,7 @@ RSpec.describe 'Projects > Merge Requests > User edits a merge request' do
 
     let(:project) do
       create(:project, :custom_repo,
-             files: { 'docs/CODEOWNERS' => "*.rb @ruby-owner\n*.js @js-owner" })
+             files: { 'docs/CODEOWNERS' => "[Backend]\n*.rb @ruby-owner\n*.js @js-owner" })
     end
 
     let(:merge_request) do
@@ -51,6 +51,7 @@ RSpec.describe 'Projects > Merge Requests > User edits a merge request' do
       visit(edit_project_merge_request_path(project, merge_request))
 
       expect(page).to have_content('*.rb')
+      expect(page).to have_content('Backend')
       expect(page).to have_link(href: user_path(ruby_owner))
     end
   end