Rename misleading test_callback_unsubscribe_after_message to test_callback_receives_message

Co-authored-by: s3rius <18153319+s3rius@users.noreply.github.com>
Agent-Logs-Url: https://github.com/taskiq-python/natsrpy/sessions/90a9e6bf-0350-4fef-ba86-7a3b5451b748

Author: Copilot

python/tests/test_subscriptions.py

@@ -77,7 +77,7 @@ async def test_iterator_drain(nats_url: str) -> None:
     await client.shutdown()
 
 
-async def test_callback_unsubscribe_after_message(nats: Nats) -> None:
+async def test_callback_receives_message(nats: Nats) -> None:
     subj = uuid.uuid4().hex
     event = asyncio.Event()