feat: try add get_group_system_msg

src/onebot11/action/group/GetGroupSystemMsg.ts

@@ -0,0 +1,11 @@
+import BaseAction from '../BaseAction';
+import { ActionName } from '../types';
+import { NTQQMsgApi } from '@/core/apis/msg';
+
+
+export class GetGroupSystemMsg extends BaseAction<void, void> {
+  actionName = ActionName.GetGroupSystemMsg;
+  protected async _handle(payload: void) {
+
+  }
+}