Uses a self-destruct receiver to kill an external process.

This test was previoulsy calling 'kill' directly, which just worked when the
tests were running as root.

Test: adb unroot && cts-tradefed run commandAndExit cts-dev -m CtsAutoFillServiceTestCase -t android.autofillservice.cts.SessionLifecycleTest#testDatasetGoesAwayWhenAutofilledAppIsKilled

Bug: 77280671
Fixes: 74618452

Change-Id: Ie35e774510b42467eade7e750e10cee7a9bb29de
4 files changed