Consider adding the current info schema version when a panic occurs in connection

## Enhancement
https://github.com/pingcap/tidb/blob/2bdc3e5d7273ab0faf9c9d5de9752e3fc503238a/server/conn.go#L956-L961

For example, this issue(https://github.com/pingcap/tidb/issues/45397) may be a panic caused by DDL, but there is no schema version information, so it is not clear which schema version the issue occurs in. If we print the schema version, we can narrow down the problem.