Remove DeviceHealthTests

This test has been deprecated and replaced by DeviceHealthChecks a
long time ago, but it was never cleaned up. On top of that, the
crash checks in this test has been broken since Q release, leaving
confusions for users: they are not actually getting the coverage
of crash checks since all the crash checks will be reporting passing
regardless of actual failures.

Bug: 193459993
Test: compile, presubmit
Change-Id: If2b2edd332be7da1d5aff27901d9c5afec2c6993
Merged-In: I71ecb89302d077a708240b1a3a7cc9749156c2d8
10 files changed