fix duplicate websocket dependency test

tests/test_duplicate_special_dependencies.py

@@ -27,13 +27,6 @@ def background_tasks(t1: BackgroundTasks, t2: BackgroundTasks) -> str:
     return "success"
 
 
-@app.get("/websocket")
-def websocket(ws1: WebSocket, ws2: WebSocket) -> str:
-    assert ws1 is not None
-    assert ws1 is ws2
-    return "success"
-
-
 @app.get("/security-scopes")
 def security_scopes(sc1: SecurityScopes, sc2: SecurityScopes) -> str:
     assert sc1 is not None
@@ -41,7 +34,12 @@ def security_scopes(sc1: SecurityScopes, sc2: SecurityScopes) -> str:
     return "success"
 
 
-client = TestClient(app)
+@app.websocket("/websocket")
+async def websocket(ws1: WebSocket, ws2: WebSocket) -> str:
+    assert ws1 is ws2
+    await ws1.accept()
+    await ws1.send_text("success")
+    await ws1.close()
 
 
 @pytest.mark.parametrize(
@@ -54,9 +52,10 @@ client = TestClient(app)
     ),
 )
 def test_duplicate_special_dependency(url: str) -> None:
-    assert client.get(url).text == '"success"'
+    assert TestClient(app).get(url).text == '"success"'
 
 
 def test_duplicate_websocket_dependency() -> None:
-    # Raises exception if connect fails.
-    client.websocket_connect("/websocket")
+    with TestClient(app).websocket_connect("/websocket") as ws:
+        text = ws.receive_text()
+        assert text == "success"