Fix pytest plugin loading for gateway tests

Author: anth-volk

projects/policyengine-api-simulation/tests/conftest.py

@@ -4,6 +4,11 @@
 import sys
 from pathlib import Path
 
+pytest_plugins = (
+    "fixtures.gateway.shared",
+    "fixtures.gateway.test_endpoints",
+)
+
 project_root = Path(__file__).parent.parent
 if str(project_root) not in sys.path:
     sys.path.insert(0, str(project_root))