Opt out HardwareTestCases from display compat

Automotive has a density scaling compatibility layer for non-automotive
applications. This can mess with the expected values of some tests, but
as HardwareTestCases aims more to test apis rather than 3p app behavior,
the density scaling doesn't make sense for this.

Bug: 413279082
Test: atest CtsHardwareTestCases
Flag: EXEMPT TEST_ONLY
Change-Id: I840514e39704797ddef167d7ccf86a363a4ebb09