fix(test): storage scrubber should only log to stdout with info

[skyzh]

Problem

As @koivunej mentioned in the storage channel, for regress test, we don't need to create a log file for the scrubber, and we should reduce noisy logs.

Summary of changes

• Disable log file creation for storage scrubber
• Only log at info level

Checklist before requesting a review

• I have performed a self-review of my code.
• If it is a core feature, I have added thorough tests.
• Do we need to implement analytics? if so did you add the relevant metrics to the dashboard?
• If this PR requires public announcement, mark it with /release-notes label and add several sentences in this section.

Checklist before merging

• Do not forget to reformat commit message to not include the above checklist

[github-actions]

5038 tests run: 4874 passed, 0 failed, 164 skipped (full report)

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Flaky tests (6)

Postgres 17

• test_pg_regress[None]: debug-x86-64
• test_readonly_node_gc: debug-x86-64
• test_scrubber_physical_gc_ancestors_split: debug-x86-64
• test_subscriber_restart: debug-x86-64

Postgres 15

• test_location_conf_churn[3]: release-arm64

Postgres 14

• test_many_timelines: release-x86-64

Code coverage* (full report)

• functions: 32.2% (7477 of 23255 functions)
• lines: 50.0% (60231 of 120574 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
1e0f817 at 2024-09-24T22:45:26.199Z :recycle:}

[koivunej]

Example test report. It still has the same captured (note captured stderr and stdout files) AND forwarded logging (see test log).

Overall it's more healthy to output two (stderr, "pipe" to test log) rather than three times (stderr, "pipe" to test log, write to special file which must've been ignored by allure report generation?). I do not understand why we need to pipe it to the test log in any case. We do not do this for pageserver, for example, or safekeepers, or postgres, or storage controller.

[skyzh]

Well, probably it's because scrubber is a foreground process that gets explicitly called in the code path. I'll see how to fully remove it...

[skyzh]

added a commit 0d1e1d3

[skyzh]

should finally work now (tried different combinations of these parameters 🤣)