feat: Add draft hash check in workflow (#4251)

api/fields/workflow_fields.py

@@ -7,6 +7,7 @@ workflow_fields = {
     'id': fields.String,
     'graph': fields.Raw(attribute='graph_dict'),
     'features': fields.Raw(attribute='features_dict'),
+    'hash': fields.String(attribute='unique_hash'),
     'created_by': fields.Nested(simple_account_fields, attribute='created_by_account'),
     'created_at': TimestampField,
     'updated_by': fields.Nested(simple_account_fields, attribute='updated_by_account', allow_null=True),