Map custom fields to tags/labels in external integrations

Current implementation only allows tags to be mapped to Labels (e.g. in Trello)

As a result custom fields (e.g. predefined list of components) cannot be exported to external integrations, unless they explicitly support custom fields on their own.

Mapping to label, will allow simpler integration, require less configuration on both tools and will reduce clutter

Current alternative of using tags at Aha is not feasible, since labels are defined at the account level vs. the product level and create a lot of clutter