The four sleep-interception integration tests hardcoded a 30s per-test
timeout. That is shorter than the test rig's own per-operation timeout in CI
(60s), and each test performs more than one such operation, so under Docker
sandbox load with the CI model the tests intermittently exceed 30s and fail
(most recently 'should allow sleep < 2s' timed out on all retries, failing the
release Docker integration job). Drop the override so they use the suite's
default timeout, consistent with the other integration tests.