Simplify the boilerplate

Signed-off-by: William Fu-Hinthorn <13333726+hinthornw@users.noreply.github.com>

tests/integration_tests/test_graph.py

@@ -1,11 +1,9 @@
 import pytest
-from langsmith import unit
 
 from agent import graph
 
 
-@pytest.mark.asyncio
-@unit
+@pytest.mark.langsmith
 async def test_agent_simple_passthrough() -> None:
     res = await graph.ainvoke({"changeme": "some_val"})
     assert res is not None