refactor: 移除迁移中对 think\migration\db\Column 的依赖

database/migrations/20251010100100_create_shipping_template_rules_table.php

@@ -1,7 +1,6 @@
 <?php
 
 use think\migration\Migrator;
-use think\migration\db\Column;
 
 class CreateShippingTemplateRulesTable extends Migrator
 {

database/migrations/20251010100200_create_shipping_template_relations_table.php

@@ -1,7 +1,6 @@
 <?php
 
 use think\migration\Migrator;
-use think\migration\db\Column;
 
 class CreateShippingTemplateRelationsTable extends Migrator
 {