Add "roles" fixture to tests

tests/conftest.py

@@ -145,6 +145,21 @@ def users(app, db):
     return [user1, user2]
 
 
+@pytest.fixture()
+def roles(app, db):
+    """Create required roles."""
+    with db.session.begin_nested():
+        datastore = app.extensions["security"].datastore
+        role = datastore.create_role(
+            id=app.config["CURATIONS_MODERATION_ROLE"],
+            name=app.config["CURATIONS_MODERATION_ROLE"],
+            description="Publication request reviewers",
+        )
+
+    db.session.commit()
+    return [role]
+
+
 @pytest.fixture()
 def client_with_login(client, users):
     """A test client for the app with a logged-in user."""