Added delete endpoint and tests.

tests/app/dao/test_users_dao.py

@@ -1,6 +1,7 @@
 from sqlalchemy.exc import DataError
 from sqlalchemy.orm.exc import NoResultFound
-from app.dao.users_dao import (save_model_user, get_model_users)
+from app.dao.users_dao import (
+    save_model_user, get_model_users, delete_model_user)
 from tests.app.conftest import sample_user as create_sample_user
 from app.models import User
 
@@ -47,3 +48,9 @@ def test_get_user_invalid_id(notify_api, notify_db, notify_db_session):
         pytest.fail("DataError exception not thrown.")
     except DataError:
         pass
+
+
+def test_delete_users(notify_api, notify_db, notify_db_session, sample_user):
+    assert User.query.count() == 1
+    delete_model_user(sample_user)
+    assert User.query.count() == 0