avoid a task and a thread in the test_context_manager_used_from_diffe…

…rent_x tests

distributed/tests/test_client.py

@@ -1277,7 +1277,7 @@ async def client_2():
 @gen_cluster(client=False, nthreads=[])
 async def test_context_manager_used_from_different_tasks(s):
     c = Client(s.address, asynchronous=True)
-    await asyncio.create_task(c.__aenter__())
+    await c.__aenter__()
     with pytest.warns(
         DeprecationWarning,
         match=r"It is deprecated to enter and exit the Client context manager "
@@ -1288,17 +1288,13 @@ async def test_context_manager_used_from_different_tasks(s):
 
 def test_context_manager_used_from_different_threads(s, loop):
     c = Client(s["address"])
-    with (
-        concurrent.futures.ThreadPoolExecutor(1) as tp1,
-        concurrent.futures.ThreadPoolExecutor(1) as tp2,
+    c.__enter__()
+    with concurrent.futures.ThreadPoolExecutor(1) as tpe, pytest.warns(
+        DeprecationWarning,
+        match=r"It is deprecated to enter and exit the Client context manager "
+        "from different threads",
     ):
-        tp1.submit(c.__enter__).result()
-        with pytest.warns(
-            DeprecationWarning,
-            match=r"It is deprecated to enter and exit the Client context manager "
-            "from different threads",
-        ):
-            tp2.submit(c.__exit__, None, None, None).result()
+        tpe.submit(c.__exit__, None, None, None).result()
 
 
 def test_global_clients(loop):