`<type_traits>`: Investigate EDG issues with layout-compatibility and pointer-interconvertibility intrinsics

We have the following workarounds for internal VSO-1268984 "REPORTED: [EDG] New compiler intrinsics for Layout-compatibility and Pointer-interconvertibility Traits need to be understood by EDG":

https://github.com/microsoft/STL/blob/969b2e250df56690768fdf8344293624d6ab0d6c/stl/inc/type_traits#L1759-L1785
https://github.com/microsoft/STL/blob/969b2e250df56690768fdf8344293624d6ab0d6c/stl/inc/yvals_core.h#L1395-L1407
https://github.com/microsoft/STL/blob/969b2e250df56690768fdf8344293624d6ab0d6c/tests/std/tests/P0466R5_layout_compatibility_and_pointer_interconvertibility_traits/test.cpp#L17
https://github.com/microsoft/STL/blob/969b2e250df56690768fdf8344293624d6ab0d6c/tests/std/tests/VSO_0157762_feature_test_macros/test.compile.pass.cpp#L1001-L1017
https://github.com/microsoft/STL/blob/969b2e250df56690768fdf8344293624d6ab0d6c/tests/std/tests/VSO_0157762_feature_test_macros/test.compile.pass.cpp#L1041-L1057

This was resolved as fixed on 2022-03-07 by internal VS-PR-383770, available in VS 2022 17.2.

However, attempting to enable these features for EDG with VS 2022 17.3 Preview 3 fails with numerous compiler errors affecting several tests. We need to investigate and report these failures. The affected tests in std are:

• GH_000431_copy_move_family
• GH_000431_equal_family
• GH_000431_equal_memcmp_is_safe
• GH_000431_iter_copy_move_cat
• P0466R5_layout_compatibility_and_pointer_interconvertibility_traits

Start with the workaround locations in stl/inc/type_traits, stl/inc/yvals_core.h, and the referenced feature-test and P0466R5 tests. Enable the layout-compatibility and pointer-interconvertibility features for EDG with VS 2022 17.3 Preview 3, then examine the failures in the five listed std tests. Done means the EDG failures are understood and reported with affected tests and compiler errors.