base: Disable Sockaddr_AbstractUnix test on Mac OS
base: Disable Sockaddr_AbstractUnix test on Mac OS

Abstract sockets are a Linux-ism and are not supported on Mac OS.

Bug: 240573274
Change-Id: Ifee8fda9d117f32ccaae1d4541249abc0807d847
google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto