fix: PEP8 Style

tests/test_api.py

@@ -1,7 +1,6 @@
 import pytest
 from fastapi.testclient import TestClient
 from src.naliiabotapi.main import app
-from langchain_core.messages import HumanMessage
 
 
 @pytest.fixture
@@ -10,16 +9,19 @@ def client():
 
     return client
 
+
 def test_root(client):
     response = client.get("/")
 
     assert response.status_code == 200
 
+
 def test_health(client):
     response = client.get("/health")
 
     assert response.status_code == 200
 
+
 def test_chat(client):
     response = client.post("/chat", json={"messages": "Hello, how are you?"})