In the KanbanRenderer, the _setState method extracts the groupBy field name and tries
to get the field information from that string.
When the field is a date/datetime grouped by day/week/month/..., the field name becomes "my_date:month".
This prevents the gathering of state information since those information are stored in a dictionary with a 'my_date' key.
This commit will detect if the field has additional grouping info (:month, :week, ...) and clean the name
with a substring before accessing the state dictionary.
Aurélien Warnon
e3246845c3