skip multicast test on Darwin (holepunchto#257)

* skip multicast test on Apple

Co-authored-by: Kasper Isager Dalsgarð <kasperisager@hey.com>

---------

Co-authored-by: Kasper Isager Dalsgarð <kasperisager@hey.com>

Author: jthomas43

test/CMakeLists.txt

@@ -28,9 +28,15 @@ list(APPEND tests
 
 list(APPEND skipped_tests
   stream-write-read-perf
-  socket-send-recv-multicast
 )
 
+if(APPLE)
+  list(APPEND skipped_tests
+    socket-send-recv-multicast
+  ) 
+endif()
+
+
 foreach(test IN LISTS tests)
   add_executable(${test} ${test}.c)