refactor(代码生成): 默认端口修改为 3306

Author: lltx

src/views/gen/datasource/form.vue

@@ -102,7 +102,7 @@ const form = reactive({
   confType: 0,
   dsName: '',
   instance: '',
-  port: 0,
+  port: 3306,
   host: '',
 });