domain: revert unintended changes

[xhebox]

What problem does this PR solve?

Problem Summary: While fixing the timeout CI of #22859, I thought statistics package are stuck. Then I change the deconstruction order of sysSessionPool. But I forgot to revert it back after identifying the problem, after one month.

Check List

Tests

• Unit test
• Integration test

Release note

• No release note

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• AilinKid
• tiancaiamao

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[xhebox]

/merge

[ti-chi-bot]

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

Commit hash: 3b9697b

[ti-chi-bot]

@xhebox: Your PR was out of date, I have automatically updated it for you.

At the same time I will also trigger all tests for you:

/run-all-tests

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