Stabilize iOS SQLite reservation timeout test

[Copilot]

The failing macOS/iOS Actions job was caused by a timing-sensitive unit test, not a build break. OfflineStorageTests_SQLite.ReservedRecordsAreReleasedAfterTimeout assumed fixed sleeps were enough for all leases to expire on the simulator, which was not reliably true.

• Root cause

  • The test used a hard-coded PAL::sleep(2000) after reserving two records with different lease durations.
  • On slower or more variable iOS simulator runs, the later assertion could execute before the longest reserved_until timestamp had actually elapsed.

• Change

  • Reworked the test to wait on the recorded reservation deadlines instead of wall-clock assumptions.
  • After reserving both records, the test reads the stored records, finds the maximum reservedUntil, and waits until that deadline has passed with a small buffer.

• Effect

  • Keeps production behavior unchanged.
  • Removes simulator scheduling/timer jitter as a source of false negatives in CI.

auto records = offlineStorage->GetRecords(true, EventLatency_Unspecified, 0);
int64_t waitUntilMs = 0;
for (auto const& record : records)
{
    waitUntilMs = std::max(waitUntilMs, record.reservedUntil);
}

while (PAL::getUtcSystemTimeMs() <= waitUntilMs + 250)
{
    PAL::sleep(50);
}

[lalitb]

This should be good to merge. I won't be able to merge this, as I triggered copilot to fix the issue,