br: fix the missing retry for pd batch scan error (#33420)

[ti-srebot]

cherry-pick #33420 to release-5.1
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/33467

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

git push [email protected]:ti-srebot/tidb.git pr/33467:release-5.1-9129590f5b0c

---

What problem does this PR solve?

Issue Number: close #33419

Problem Summary:
current BR doesn't not retry ErrPDBatchScanRegion enough.

What is changed and how it works?

replace the multierr with the ErrPDBatchScanRegion

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

Fix the issue that BR not retry enough when region not consistency during restoration.

[ti-srebot]

/run-all-tests

[ti-srebot]

@3pointer you're already a collaborator in bot's repo.