Fix flaky test tests/test_trigger_preflight_model.py::test_the_model_request_never_carries_the_webhook_secret_or_the_key

The merge lane saw `tests/test_trigger_preflight_model.py::test_the_model_request_never_carries_the_webhook_secret_or_the_key` fail and then pass on a rerun of the same tree. - Test: `tests/test_trigger_preflight_model.py::test_the_model_request_never_carries_the_webhook_secret_or_the_key` - Tree: `336500b9600a16cbb307ba31a69997424d5b7820` - Lane task: 9614 - Flake record: 01a16cd3-952f-71e9-abb2-49eef1b07e4d Make it deterministic; do not delete it unless it tests nothing. - Also flaky, same file: `tests/test_trigger_preflight_model.py::test_the_triggers_own_key_wins_over_the_platform_key` (tree `336500b9600a16cbb307ba31a69997424d5b7820`, lane task 9614, flake record 01a16cd3-95f6-7e7b-a570-84d92ff848a1) - Also flaky, same file: `tests/test_trigger_preflight_model.py::test_no_key_of_its_own_falls_back_to_the_platform_key` (tree `336500b9600a16cbb307ba31a69997424d5b7820`, lane task 9614, flake record 01a16cd3-96a2-7790-bfdb-053781988469) - Also flaky, same file: `tests/test_trigger_preflight_model.py::test_neither_key_is_a_counted_failure_at_run` (tree `336500b9600a16cbb307ba31a69997424d5b7820`, lane task 9614, flake record 01a16cd3-987c-7986-8123-e46a44b89521) - Also flaky, same file: `tests/test_trigger_preflight_model.py::test_an_unusable_key_is_a_counted_failure_not_a_retry[another_person]` (tree `336500b9600a16cbb307ba31a69997424d5b7820`, lane task 9614, flake record 01a16cd3-9a8d-7054-8bbb-70a792d96174) - Also flaky, same file: `tests/test_trigger_preflight_model.py::test_an_unusable_key_is_a_counted_failure_not_a_retry[the_org]` (tree `336500b9600a16cbb307ba31a69997424d5b7820`, lane task 9614, flake record 01a16cd3-9c48-7a8e-86a1-e07316cbad07) - Also flaky, same file: `tests/test_trigger_preflight_model.py::test_a_provider_outage_is_unavailable_and_retried[timeout]` (tree `336500b9600a16cbb307ba31a69997424d5b7820`, lane task 9614, flake record 01a16cd3-9d93-7369-b2ee-268177ea5b3a) - Also flaky, same file: `tests/test_trigger_preflight_model.py::test_a_provider_outage_is_unavailable_and_retried[connection]` (tree `336500b9600a16cbb307ba31a69997424d5b7820`, lane task 9614, flake record 01a16cd3-9e37-7c2b-999e-d06e1dee56c8) - Also flaky, same file: `tests/test_trigger_preflight_model.py::test_a_provider_outage_is_unavailable_and_retried[429]` (tree `336500b9600a16cbb307ba31a69997424d5b7820`, lane task 9614, flake record 01a16cd3-9f37-7b73-bb78-fc0ae5b7dd5b) - Also flaky, same file: `tests/test_trigger_preflight_model.py::test_a_provider_outage_is_unavailable_and_retried[500]` (tree `336500b9600a16cbb307ba31a69997424d5b7820`, lane task 9614, flake record 01a16cd3-a020-77e3-832c-67d9342bd330) - Also flaky, same file: `tests/test_trigger_preflight_model.py::test_a_provider_outage_is_unavailable_and_retried[529]` (tree `336500b9600a16cbb307ba31a69997424d5b7820`, lane task 9614, flake record 01a16cd3-a0fb-7b31-99b0-a2ca109a5b22) - Also flaky, same file: `tests/test_trigger_preflight_model.py::test_a_provider_refusal_is_a_counted_failure[400]` (tree `336500b9600a16cbb307ba31a69997424d5b7820`, lane task 9614, flake record 01a16cd3-a207-7446-a64d-1336b4927db4) - Also flaky, same file: `tests/test_trigger_preflight_model.py::test_a_provider_refusal_is_a_counted_failure[401]` (tree `336500b9600a16cbb307ba31a69997424d5b7820`, lane task 9614, flake record 01a16cd3-a2d4-729b-850f-cecd8808adc9) - Also flaky, same file: `tests/test_trigger_preflight_model.py::test_malformed_model_output_fails_through_the_shared_parser[Sure_` (tree `336500b9600a16cbb307ba31a69997424d5b7820`, lane task 9614, flake record 01a16cd3-a3b0-7019-852e-760017a2a170) - Also flaky, same file: `tests/test_trigger_preflight_model.py::test_malformed_model_output_fails_through_the_shared_parser[__run_:` (tree `336500b9600a16cbb307ba31a69997424d5b7820`, lane task 9614, flake record 01a16cd3-a47b-72bc-aadd-f9da4d4b877c) - Also flaky, same file: `tests/test_trigger_preflight_model.py::test_malformed_model_output_fails_through_the_shared_parser[__items_:` (tree `336500b9600a16cbb307ba31a69997424d5b7820`, lane task 9614, flake record 01a16cd3-a566-736c-b6ab-752c22743e94) - Also flaky, same file: `tests/test_trigger_preflight_model.py::test_a_reply_cut_off_at_the_token_limit_is_a_counted_failure` (tree `336500b9600a16cbb307ba31a69997424d5b7820`, lane task 9614, flake record 01a16cd3-a6a2-7346-9226-c6752f3d8c64)

Duplicate: the preflight-model flakes came from test_tenant_receive patching the global time.monotonic, which killed gw1's TestClient portals. Task 9620 already merged the same fix (0bd1084a1). Reproduced as resolved on develop: 49 passed. No PR. Memory: proposed 1 gotcha.