EHN: add "role" property to QueryTemplate

src/caosdb/common/models.py

@@ -1267,6 +1267,7 @@ class QueryTemplate():
     def __init__(self, id=None, name=None, query=None, description=None):  # @ReservedAssignment
 
         self.id = (int(id) if id is not None else None)
+        self.role = "QueryTemplate"
         self.name = name
         self.description = description
         self.query = query