CameraITS: Increase error margin for test_tonemap_sequence

LSC (Lens Shading Correction) is FAST for manual capture. And because
each manual request from ITS triggers a configure_streams, and HAL may
run 3A after configure_streams, the LSC applied by HAL may be slightly
different for manual controls with the same setting.

Increase the error margin to accomodate this.

Bug: 29249410
Change-Id: Ifdfe6034b1ef569e97b5a072ea3298b67ef05367
1 file changed