fix flakey test SoundTriggerMiddlewareTest

existing timeout in FakeLatencyTracker is too short for passing the test
on emulators.

This change is a stop gap fix, and there will be a follow up to remove
the DeviceConfig dependency on FakeLatencyTracker all together.

Test: atest SoundTriggerMiddlewareTest
Bug: 275113847
Change-Id: I834d264caf59a07d452b1287bb33181de8cd7cea