Flaky: MailShutdownGraceTests.A_grace_expiry_leaves_the_row_eligible_without_counting_an_attempt #1205

Failed once in CI run 37594852123 (job unit) on main e951449 — a commit that only added runtime TypeScript modules and their tests — and passed in run 37598186578 on 251e4e2 with no change to Rask.Mailing.

Test: Rask.Mailing.Tests.MailShutdownGraceTests.A_grace_expiry_leaves_the_row_eligible_without_counting_an_attempt.

Looks timing dependent (grace expiry measured against a real clock under a loaded runner). To do: read the first run's failure message, replace the real delay with a controllable clock or a deterministic signal.