Workflow library task functionality will no longer be supported. There is no replacement for this functionality. The purpose of the "workflow library task" was to allow for the creation of a workflow that could be re-used.
There is no replacement for this functionality; however,any workflow definition json can be saved and resubmitted later.
See the Deprecation Schedule for all deprecated GBDX services and resources.
Contact GBDX Support if you have questions or need assistance.