ddl: fix bug that new partition will not set the placement policy after truncated

[lcwangchao]

What problem does this PR solve?

Issue Number: close #44031

Problem Summary:

see issue

What is changed and how it works?

Also update placement settings for the table's group after truncated

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.

ddl: fix bug that new partition will not set the placement policy after truncated

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• Defined2014
• xhebox

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[xhebox]

How did he found this bug?

[lcwangchao]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 6b24d8c

[hawkingrei]

/retest

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-6.1: #44060.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-6.5: #44061.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.1: #44062.