Fixes close/reopen quick actions preview for issues and merge_requests

Close/reopen quick actions preview wasn't shown properly, now the
preview is shown as expected.

app/serializers/issue_entity.rb

@@ -42,6 +42,6 @@ class IssueEntity < IssuableEntity
   end
   expose :preview_note_path do |issue|
-    preview_markdown_path(issue.project, quick_actions_target_type: 'Issue', quick_actions_target_id: issue.id)
+    preview_markdown_path(issue.project, quick_actions_target_type: 'Issue', quick_actions_target_id: issue.iid)
   end
 end

app/serializers/merge_request_widget_entity.rb

@@ -222,7 +222,7 @@ class MergeRequestWidgetEntity < IssuableEntity
   end
   expose :preview_note_path do |merge_request|
-    preview_markdown_path(merge_request.project, quick_actions_target_type: 'MergeRequest', quick_actions_target_id: merge_request.id)
+    preview_markdown_path(merge_request.project, quick_actions_target_type: 'MergeRequest', quick_actions_target_id: merge_request.iid)
   end
   expose :merge_commit_path do |merge_request|

changelogs/unreleased/52669-fixes-quick-actions-preview.yml

+---
+title: Fixes close/reopen quick actions preview for issues and merge_requests
+merge_request: 22343
+author: Jacopo Beschi @jacopo-beschi
+type: fixed

spec/support/features/issuable_quick_actions_shared_examples.rb

@@ -77,6 +77,15 @@ shared_examples 'issuable record that supports quick actions in its description
         expect(issuable.labels).to eq [label_bug]
         expect(issuable.milestone).to eq milestone
       end
+
+      it 'removes the quick action from note and explains it in the preview' do
+        preview_note("Awesome!\n\n/close")
+
+        expect(page).to have_content 'Awesome!'
+        expect(page).not_to have_content '/close'
+        issuable_name = issuable.is_a?(Issue) ? 'issue' : 'merge request'
+        expect(page).to have_content "Closes this #{issuable_name}."
+      end
     end
     context 'with a note containing only commands' do