forbid looping tasks with an interval of 0
This severly harm the server, and generally are the result of a
baaad configuration file. We want to stop the server asap when
this is detected to give people a chance to fix the configuration.
# type attribute might already be there if migrating from
# version < 3.5 to version >= 3.5.3, BaseTransition being added
# in bootstrap_migration
if versions_map['cubicweb'][0] >= (3, 5, 0):
add_attribute('BaseTransition', 'type')
sync_schema_props_perms('state_of')
sync_schema_props_perms('transition_of')