fix: 处理null问题

buhuazhen

2026-06-01 facbfd2b1a0eb1ea971b699def8c85a43c5fa7fa

 src/main/java/com/ruoyi/collaborativeApproval/dto/SealApplicationManagementDTO.java

@@ -8,4 +8,7 @@
    private String createUserName;
    //所属部门
    private String department;

    //审批人姓名
    private String approveUserName;
}