Basic fast_import python test

[NanoBjorn]

We did not have any tests on fast_import binary yet.

In this PR I have introduced:

• FastImport class and tools for testing in python
• basic test that runs fast import against vanilla postgres and checks that data is there

Should be merged after #10251

[jcsp]

Perhaps makes sense to make this an extension to test_pgdata_import_smoke, which has this comment currently:

    # We have a Postgres data directory now.
    # Make a localfs remote storage that looks like how after `fast_import` ran.
    # TODO: actually exercise fast_import here

[NanoBjorn]

Just thought that it might not worth doing it all in the same test due to increased complexity -> more complicated debugging if something is failing. Right now it is using vanilla postgres pgdata as we do in fast import, so it should be enough for testing pageserver part.

Moved mine simple test to the same file, but will keep test_pgdata_import_smoke the same. Also added a todo to test full import flow separately, which will complement test_pgdata_import_smoke and test_fast_import_binary, but not complicate any of those.

[NanoBjorn]

WDYT?

[github-actions]

6460 tests run: 6170 passed, 0 failed, 290 skipped (full report)

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Flaky tests (2)

Postgres 17

• test_physical_replication_config_mismatch_too_many_known_xids: debug-x86-64

Postgres 16

• test_physical_replication_config_mismatch_max_locks_per_transaction: release-arm64

Test coverage report is not available

_{The comment gets automatically updated with the latest test results
e856fae at 2025-01-06T20:50:28.045Z :recycle:}