Replace $ with QWC username in datasource filter

Author: manisandro

src/data_service.py

@@ -591,7 +591,7 @@ def dataset_edit_permissions(self, dataset, identity, translator, write):
             "dataset": resource['name'],
             "database_read": resource['db_url'],
             "database_write": resource.get('db_write_url', resource['db_url']),
-            "datasource_filter": resource.get('datasource_filter', None),
+            "datasource_filter": resource.get('datasource_filter', None).replace('$QWC_USERNAME$', get_username(identity)),
             "schema": resource['schema'],
             "table_name": resource['table_name'],
             "primary_key": resource['primary_key'],