cherry-pick #34134 to release-2.1
You can switch your code base to this Pull Request by using git-extras:

# In tidb repo:
git pr https://github.com/pingcap/tidb/pull/34183

After apply modifications, you can push your change to this PR via:

git push git@github.com:ti-srebot/tidb.git pr/34183:release-2.1-d3a02f416aaa

What problem does this PR solve?

Issue Number: close #34180
See https://github.com/pingcap/enterprise-plugin/issues/68

Problem Summary:

What is changed and how it works?

Let flush statement commit the current transaction.

begin;
delete from mysql.tidb_audit_table_access ...
flush tidb plugins audit;
commit;

After deleting the record from mysql.tidb_audit_table_access, the audit log plugin still working,
that's because flush tidb plugins audit; doen't see the uncommitted delete statement.

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

Flush statement now trigger an implicit commit when called inside a transaction