vibrator/vts: Update tests for short durations

Add minimum wait time for effect completion. Effects with short
durations were not completing in time with current wait time estimation.

Bug: 240946208
Test: Ran updated tests
Change-Id: I40f65244c3478fb2f0a3b84c3991313ad5e28cd9
Signed-off-by: Nathan Kulczak <nathankulczak@google.com>