BackupTS column of Restore Statement is not right in implementation

[IANTHEREAL]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

In migrate data from one tidb to another tidb tourist

BackupTS column of Restore Statement is not right in implementation, in fact the value 431434141450371074is restored cluster ts, not backup ts

2. What did you expect to see? (Required)

Intuitively, backup ts should be the snapshot ts corresponding to the snapshot backup. So I suggest to refine the output schema. Take migrate data from one tidb to another tidb tourist as an example, it should be

mysql> RESTORE DATABASE * FROM 's3://backup?access-key=minio&secret-access-key=miniostorage&endpoint=http://${HOST_IP}:6060&force-path-style=true';

+------------+-----------+-------------------+-------------------+-------------+-------------+
| Backup Storage | Size   | BackupTS          |Cluster TS        |Queue Time   |Execution Time|
+---------- --+-----------+------------------+-------------------+-------------+-------------+
| s3://backup  | 10315858 |431434047157698561|431434141450371074| ***          | **          |
+------------+-----------+-------------------+-------------------+-------------+-------------+
1 row in set (41.85 sec)

3. What did you see instead (Required)

4. What is your TiDB version? (Required)

[MoCuishle28]

/assign MoCuishle28