TV: Change keycode in unhandled event test

Change the keycode used in testOnUnhandledInputEventListener from
KEYCODE_BUTTON_16 to KEYCODE_0 as the previous keycode seems
to be handled now.

Bug: 234333896
Bug: 333334664
Test: atest android.media.tv.cts.TvViewTest#testOnUnhandledInputEventListener
Change-Id: Idb4141b50e0e3d3d360dbdd7d4b7766529f2add9
1 file changed