Disable key repeat for PendingKey_IsDroppedWhileMotionIsProcessedAndNewTouchComesIn test

This test occasionally fails because the dispatcher generates a key
repeat. This key repeat races with the other timeouts that are used in
this test, so it is only occasionally generated.

Since this test isn't related to key repeats, attempt to deflake it by
disabling key repeats.

Bug: 294547658
Test: TEST=inputflinger_tests; m $TEST && $ANDROID_HOST_OUT/nativetest64/$TEST/$TEST --gtest_filter="*PendingKey_IsDroppedWhileMotionIsProcessedAndNewTouchComesIn"
Test: m checkinput
Change-Id: I75cae28b07011ddaeb9165494e27fc17a2ef36f5