Fix references to asyncio

Author: pquentin

test_elasticsearch/test_async/test_server/test_helpers.py

@@ -128,7 +128,7 @@ async def async_gen():
             yield {"answer": 2, "_id": 0}
             yield {"answer": 1, "_id": 1}
             yield helpers.BULK_FLUSH
-            await asyncio.sleep(0.5)
+            await anyio.sleep(0.5)
             yield {"answer": 2, "_id": 2}
 
         timestamps = []
@@ -145,7 +145,7 @@ async def test_timeout_flushes(self, async_client):
         async def async_gen():
             yield {"answer": 2, "_id": 0}
             yield {"answer": 1, "_id": 1}
-            await asyncio.sleep(0.5)
+            await anyio.sleep(0.5)
             yield {"answer": 2, "_id": 2}
 
         timestamps = []