exchange partition lead to inaccurate stats_meta

[hawkingrei]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

there might be an issue with transactions updating the row count and modify_count

when we exchange partition,

We will read this value and then perform operations on it. However, the problem is that he forgot to use "FOR UPDATE" when reading it to lock the data. As a result, subsequent updates may corrupt the data, leading to incorrect statistical values.

In scenarios with frequent write and delete operations, this can potentially lead to significant discrepancies

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

3. What did you see instead (Required)

4. What is your TiDB version? (Required)