Use IME that supports handwriting in HandwritingInitiatorPerfTest

Without this, HandwritingInitiator doesn't do much since it only tracks
motion events if handwriting is available.

This change causes some test timing metrics to increase, as expected.

Bug: 238233219
Test: atest HandwritingInitiatorPerfTest
Change-Id: I58aad7ed7d0104c65279fc2085de073c126c1edb