only recreate client context in async version

Author: sleepyStick

test/__init__.py

@@ -860,6 +860,9 @@ def max_message_size_bytes(self):
 
 
 def recreate_client_context():
+    if _IS_SYNC:
+        # sync tests don't need to recreate a client context
+        return
     global client_context
     teardown()
     client_context = ClientContext()

test/asynchronous/__init__.py

@@ -862,6 +862,9 @@ async def max_message_size_bytes(self):
 
 
 async def recreate_client_context():
+    if _IS_SYNC:
+        # sync tests don't need to recreate a client context
+        return
     global async_client_context
     await async_teardown()
     async_client_context = AsyncClientContext()