fix(test): drop subscription when test completes

[skyzh]

Problem

This pull request mitigates #6969, but the longer-term problem is that we cannot properly stop Postgres if there is a subscription.

Summary of changes

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]

2490 tests run: 2368 passed, 0 failed, 122 skipped (full report)

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Flaky tests (4)

Postgres 16

• test_logical_replication: release
• test_timeline_deletion_with_files_stuck_in_upload_queue: debug
• test_empty_tenant_size: release

Postgres 14

• test_pg_regress[4]: debug

Code coverage* (full report)

• functions: 28.8% (6982 of 24255 functions)
• lines: 47.4% (42878 of 90535 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
94005ce at 2024-03-06T16:06:09.961Z :recycle:}

[save-buffer]

It's strange that test_logical_replication doesn't have this issue

[knizhnik]

It's strange that test_logical_replication doesn't have this issue

test_logical_replication use Vanilla Postgres as subscriber

[skyzh]

Per discussion at the compute meeting, we can mitigate this issue first by dropping the replication subscription and look into the root cause later. @save-buffer would you please take a look? Thanks a lot!

[save-buffer]

Thanks for figuring this one out. Did we ever figur eout why it was only pg15?

[skyzh]

I have no idea, and we still need to investigate the root cause in the future 😅