Fix delivery ID assertion in verify_signature test

Author: manascb1344

tests/test_app.py

@@ -199,10 +199,11 @@ async def test_verify_signature_valid():
     from app import verify_signature
 
     body = b'{"test": true}'
-    request = _make_request(body)
+    delivery_id = _next_delivery_id()
+    request = _make_request(body, delivery_id=delivery_id)
 
-    delivery_id = await verify_signature(request, body)
-    assert delivery_id == "test-delivery-123"
+    result = await verify_signature(request, body)
+    assert result == delivery_id
 
 
 @pytest.mark.asyncio