API: Fixed attachment list showing items on deleted pages

List endpoint would show attachments for pages which were in the recycle
bin. This adds a deleted_at filter for related pages to the core
permission application query.
Added test to cover.

For #6194

app/Permissions/PermissionApplicator.php

@@ -198,6 +198,7 @@ class PermissionApplicator
                     ->leftJoin('entity_page_data', 'entities.id', '=', 'entity_page_data.page_id')
                     ->whereColumn('entities.id', '=', $fullPageIdColumn)
                     ->where('entities.type', '=', 'page')
+                    ->whereNull('entities.deleted_at')
                     ->where(function (QueryBuilder $query) {
                         $query->where('entity_page_data.draft', '=', false)
                             ->orWhere(function (QueryBuilder $query) {

tests/Api/AttachmentsApiTest.php

@@ -61,6 +61,22 @@ class AttachmentsApiTest extends TestCase
         ]]);
     }
 
+    public function test_index_does_not_show_attachments_for_pages_in_recycle_bin()
+    {
+        $this->actingAsApiEditor();
+        $page = $this->entities->page();
+        $attachment = $this->createAttachmentForPage($page, [
+            'name'     => 'My test attachment',
+            'external' => true,
+        ]);
+        $this->entities->sendToRecycleBin($page);
+
+        $resp = $this->getJson("{$this->baseEndpoint}?filter[id]={$attachment->id}");
+
+        $resp->assertJsonCount(0, 'data');
+        $resp->assertJsonPath('total', 0);
+    }
+
     public function test_create_endpoint_for_link_attachment()
     {
         $this->actingAsApiAdmin();