Enable c10d trampoline tests on MacOS (pytorch#67205)

Summary:
Pull Request resolved: pytorch#67205

cc pietern mrshenli pritamdamania87 zhaojuanmao satgera rohan-varma gqchen aazzolini osalpekar jiayisuse SciPioneer H-Huang

Test Plan: Imported from OSS

Reviewed By: rohan-varma

Differential Revision: D31916705

Pulled By: mrshenli

fbshipit-source-id: 440d319959796d01c637c277706eeab127d9bde7

test/distributed/test_c10d_common.py

@@ -6,7 +6,6 @@
 import tempfile
 import threading
 import time
-import unittest
 from datetime import timedelta
 from itertools import product
 from sys import platform
@@ -792,10 +791,6 @@ def _store_barrier(self, name):
         else:
             store.add(key, 1)
 
-    @unittest.skipIf(
-        common.IS_MACOS,
-        "Python c10d extension is not yet supported on MacOS"
-    )
     def test_collectives(self):
         dist.Backend.register_backend("dummy", PythonProcessGroupTest.create_dummy)
 
@@ -830,10 +825,6 @@ def test_collectives(self):
         self._store_barrier("test_collectives")
         dist.destroy_process_group()
 
-    @unittest.skipIf(
-        common.IS_MACOS,
-        "Python c10d extension is not yet supported on MacOS"
-    )
     def test_send_recv(self):
         dist.Backend.register_backend("dummy", PythonProcessGroupTest.create_dummy)