False positive of assertion when pessimistic lock is lost

[ekexium]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

2 sessions both with @@tidb_constraint_check_in_place_pessimistic = 0
session 1: begins a pessimistic transaction select for update read a non-existent row
session 2: begins a pessimistic transaction, insert 2 rows, one of which is the row read above. Commit.
session 1: read the second row session just inserted to update its for_update_ts, and then update the row it has locked before. Commit.

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

No assertion error.

3. What did you see instead (Required)

session 1: assertion failure

4. What is your TiDB version? (Required)

6.3.0