Fix flaky TestValidateEvictionStatusUpdate/mark_active_and_started

The test's oldInput used metav1.Now() (wall clock) for Responder[0].StartTime
while input used clock.Now() (fake clock initialized from time.Now()). On Windows,
where the system clock resolution is ~15ms, both calls could return the same
timestamp, making oldInput and input semantically equal and triggering the
"Expected oldInput and input to differ" assertion.

Use empty oldInput (with 0 responders) to guarantee a deterministic difference
between old and new state.

Signed-off-by: Lukasz Wojciechowski <l.wojciechow@partner.samsung.com>