NotifyReceiver 添加一个 sign 字段, 目前是 dingding 的 webhook 使用

mgr/src/main/java/cn/reghao/devops/mgr/admin/sys/model/po/NotifyReceiver.java

@@ -27,6 +27,7 @@ public class NotifyReceiver extends BaseEntity {
     private String type;
     @NotBlank
     private String url;
+    private String sign;
     private Boolean setdefault;
 
     public NotifyReceiver() {