Increase wait_lsn_timeout in test_wal_receiver.py

[petuhovskiy]

In these tests wait_lsn_timeout was set to 1s which was too low. If something blinks (sk<->ps connection, sk activation, broker) during the test, the test will likely fail because of that. This commit changes the timeout to 3s which should be more stable.

I noticed this error when I made a PR for timeline_manager in safekeepers, this test was flaking because timeline activation was not instant.

[github-actions]

2904 tests run: 2784 passed, 3 failed, 117 skipped (full report)

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Failures on Postgres 16

• test_pageserver_lsn_wait_error_start: debug

Failures on Postgres 15

• test_pageserver_lsn_wait_error_start: debug

Failures on Postgres 14

• test_pageserver_lsn_wait_error_start: debug

# Run all failed tests locally:
scripts/pytest -vv -n $(nproc) -k "test_pageserver_lsn_wait_error_start[debug-pg14] or test_pageserver_lsn_wait_error_start[debug-pg15] or test_pageserver_lsn_wait_error_start[debug-pg16]"

Flaky tests (4)

Postgres 16

• test_pageserver_lsn_wait_error_safekeeper_stop: debug

Postgres 15

• test_location_conf_churn[3]: release
• test_pageserver_lsn_wait_error_safekeeper_stop: debug

Postgres 14

• test_pageserver_lsn_wait_error_safekeeper_stop: debug

Test coverage report is not available

_{The comment gets automatically updated with the latest test results
7fcc31c at 2024-06-21T15:49:21.411Z :recycle:}

[petuhovskiy]

Hmm, apparently increased timeout fails test_pageserver_lsn_wait_error_start. Not sure why.