The test used a 5ms TTL with a 10ms wall-clock sleep to simulate cache
expiry. On loaded CI runners (Azure eastus), the repull HTTP round-trip
plus disk I/O for Store easily exceeded 5ms, causing the freshly written
cache entry to also appear expired when Load was called immediately after,
producing a spurious 'cache expired' error.
HubCache already exposes a nowFn field for deterministic time injection.
Replace the sleep-based approach with a nowFn that advances the clock 2
hours, making the initial entry appear expired to Apply while keeping the
freshly re-stored entry (retrieved_at ≈ now+2h, TTL=1h) valid for the
final assertion.
5fa0cff274