Python: replace asyncio.sleep with anyio.sleep in async tests (#4682)

fix: replace asyncio.sleep with anyio.sleep in async tests

Fixes RuntimeError: no running event loop by using anyio.sleep()
instead of asyncio.sleep() in test_async_client.py test cases.

Signed-off-by: affonsov <67347924+affonsov@users.noreply.github.com>

Author: affonsov

python/tests/async_tests/test_async_client.py

@@ -11238,10 +11238,7 @@ async def test_hexpire(self, glide_client: TGlideClient):
         result = await glide_client.hexpire(key, 1, [field1])  # 1 second
         assert result == [1]  # Should set expiration
 
-        # Wait a moment and check if it's still there or expired
-        import asyncio
-
-        await asyncio.sleep(0.1)  # Small delay
+        await anyio.sleep(0.1)  # Small delay
         ttl_result = await glide_client.httl(key, [field1])
         assert (
             ttl_result[0] == 1 or ttl_result[0] == -2
@@ -11411,9 +11408,7 @@ async def test_hpexpire(self, glide_client: TGlideClient):
         assert result == [1]  # Should set expiration
 
         # Wait a moment and check if it's still there or expired
-        import asyncio
-
-        await asyncio.sleep(0.1)  # Small delay
+        await anyio.sleep(0.1)  # Small delay
         ttl_result = await glide_client.httl(key, [field1])
         assert (
             ttl_result[0] == 1 or ttl_result[0] == -2