Fix default for Operation.

accountant/api/models/operations.py

@@ -14,6 +14,8 @@
     You should have received a copy of the GNU Affero General Public License
     along with Accountant.  If not, see <http://www.gnu.org/licenses/>.
 """
+from datetime import date
+
 import arrow
 
 from sqlalchemy import func, case, desc, true, false, text
@@ -28,7 +30,7 @@ class Operation(db.Model):
     operation_date = db.Column(
         db.Date,
         nullable=False,
-        default=arrow.now().date(),
+        default=date.today,
         server_default=func.current_date(),
         index=True
     )