bugfix role assignments

pybis/src/python/pybis/role_assignment.py

@@ -31,9 +31,10 @@ class RoleAssignment(OpenBisObject):
         return "{}".format(self.get('role'))
 
     def delete(self, reason='no reason specified'):
-        self.openbis.delete_entity(
-            entity='RoleAssignment', id=self.id, 
-            reason=reason, id_name='techId'
-        ) 
+        self.openbis.delete_openbis_entity(
+            entity='roleAssignment',
+            objectId=self._id,
+            reason= reason
+        )
         if VERBOSE:
             print("RoleAssignment role={}, roleLevel={} successfully deleted.".format(self.role, self.roleLevel))