需求详情无分组返回0

app/Http/Resources/API/RequirementResource.php

@@ -19,7 +19,7 @@ class RequirementResource extends JsonResource
             'status' => $this->status,
             'asset_id' => $this->asset_id,
             'plan_id' => $this->plan_id,
-            'requirement_group_id' => $this->requirement_group_id,
+            'requirement_group_id' => $this->requirement_group_id ?? 0,
             'requirement_group' => new RequirementGroupResource($this->group),
             'asset' => new SimpleAssetResource($this->asset),
             'reviewed_by' => $this->reviewed_by,