GH-5: Add a sample test case for '/auth' route

Author: ArtyomVancyan

tests/test_oauth2_middleware.py

@@ -22,7 +22,8 @@
 })
 
 
-
-def test_read_main():
-    response = client.get("/")
-    assert response.status_code == 404
+@pytest.mark.anyio
+async def test_auth_redirect():
+    async with AsyncClient(app=app, base_url="http://test") as client:
+        response = await client.get("/oauth2/github/auth")
+        assert response.status_code == 303  # Redirect