docs: migrate to lifespan and update associated tests

docs_src/app_testing/tutorial003.py

@@ -0,0 +1,28 @@
+from contextlib import asynccontextmanager
+
+from fastapi import FastAPI
+from fastapi.testclient import TestClient
+
+items = {}
+
+
+@asynccontextmanager
+async def lifespan(app: FastAPI):
+    items["foo"] = {"name": "Fighters"}
+    items["bar"] = {"name": "Tenders"}
+    yield
+
+
+app = FastAPI(lifespan=lifespan)
+
+
+@app.get("/items/{item_id}")
+async def read_items(item_id: str):
+    return items[item_id]
+
+
+def test_read_items():
+    with TestClient(app) as client:
+        response = client.get("/items/foo")
+        assert response.status_code == 200
+        assert response.json() == {"name": "Fighters"}

tests/test_tutorial/test_testing/test_tutorial003.py

@@ -1,7 +1,6 @@
 import pytest
 
-
 def test_main():
-    with pytest.warns(DeprecationWarning):
-        from docs_src.app_testing.tutorial003_py310 import test_read_items
+    from docs_src.app_testing.tutorial003_py310 import test_read_items
     test_read_items()
+