refactor: add casbin adapter to common to avoid build failing

Author: mariajgrimaldi

openedx_authz/settings/common.py

@@ -17,6 +17,9 @@ def plugin_settings(settings):
         settings: The Django settings object
     """
     # Add external third-party apps to INSTALLED_APPS
+    casbin_adapter_app = "casbin_adapter.apps.CasbinAdapterConfig"
+    if casbin_adapter_app not in settings.INSTALLED_APPS:
+        settings.INSTALLED_APPS.append(casbin_adapter_app)
 
     # Add Casbin configuration
     settings.CASBIN_MODEL = os.path.join(