c2_e2e_test: ignore configuration changes

Update the E2eTestActivity manifest so that it handles configuration
changes itself, and just ignore them. This prevents the activity from
being recreated, which destroys the test surface.

Bug: 206342802
Test: tast run octopus arc.VideoDecodeAccelPerf.*
Change-Id: Ie48cf0650424c9f641c2770b3127f75e6407c01d
(cherry picked from commit 0127892edd2d5f62623e14db20b1a023850e0667)