[lldb] Skip TestPointerToMemberTypeDependingOnParentSize on Windows and GCC

The test added in D100977 is failing to compile on these platforms. This seems
to be caused by GCC, MSVC and Clang@Windows rejecting the code because
`ToLayout` isn't complete when pointer_to_member_member is declared (even though
that seems to be valid code).

This also reverts the test changes in the lazy-loading test from D100977 as
that failed for the same reason.