Only churn rows once in test_scrubber_physical_gc_ancestors

[arpad-m]

Problem

PR #10457 was supposed to fix the flakiness of test_scrubber_physical_gc_ancestors, but instead it made it even more flaky. However, the original error causes disappeared, now to be replaced by key not found errors.

See this for a longer explanation: #10391 (comment)

Solution

This does one churn rows after all compactions, and before we do any timeline gc's. That way, we remain more accessible at older lsn's.

[github-actions]

7370 tests run: 6984 passed, 0 failed, 386 skipped (full report)

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Flaky tests (6)

Postgres 17

• test_explain_with_lfc_stats: release-arm64
• test_subscriber_synchronous_commit: release-x86-64
• test_metrics_normal_work: debug-x86-64

Postgres 15

• test_metrics_normal_work: release-x86-64, release-arm64

Postgres 14

• test_metrics_normal_work: release-arm64

Code coverage* (full report)

• functions: 33.5% (8493 of 25334 functions)
• lines: 49.3% (71376 of 144677 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
4dc9614 at 2025-01-22T19:49:01.608Z :recycle:}