Fix nil pointer dereference in ListRules method of WAF service

- Update condition to check for nil RuleCategoryStatus before accessing Status
- Ensure safe handling of WAF service rule categories

internal/service/waf.go

@@ -877,7 +877,7 @@ func (s *wafService) ListRules(ctx context.Context, regionCode, namespace, gatew
 	if err != nil {
 		return nil, fmt.Errorf("failed to get waf service: %v", err)
 	}
-	if wafService.RuleCategoryStatus.Status == 1 {
+	if wafService.RuleCategoryStatus != nil && wafService.RuleCategoryStatus.Status == 1 {
 		for _, category := range ruleCategories {
 			for _, categoryID := range wafService.RuleCategoryStatus.CategoryID {
 				if category.CategoryID == categoryID {