Fix N+1 test of pipeline seed

What does this MR do?

This MR adds a warm-up stage for N+1 test.

We need it for checking the actual result because there are some non-related SQL queries like;

• InternalId Load
• InternalId Update
• Ci::Ref Load

And those queries may lead us to false positives. The first control state always has SQL queries more than it should.

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I run into this after opening this MR !60805 (closed). Then realized that there is something wrong with the test.

Does this MR meet the acceptance criteria?

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