Stabilize backend route tests

backend/tests/test_artifacts.py

@@ -1,9 +1,5 @@
 from pathlib import Path
 
-from fastapi.testclient import TestClient
-
-from app.main import app
-
 
 def test_project_var_artifact_path_is_served(tmp_path, monkeypatch):
     from app import main
@@ -30,6 +26,7 @@ def test_project_var_artifact_path_is_served(tmp_path, monkeypatch):
     )
     monkeypatch.setattr(main, "settings", patched)
 
-    response = TestClient(app).get("/api/artifacts/var/uploads/datasets/case/labels/label.txt")
-    assert response.status_code == 200
-    assert response.text == "ok"
+    response = main.api_artifact("var/uploads/datasets/case/labels/label.txt")
+
+    assert Path(response.path) == artifact
+    assert response.media_type == "text/plain"