unexpected behavior in exclude/include in workflow api funtionality

[porteratzo]

Describe the bug
In collaborator workflow steps, if the first exclude/include argument is not in the collaborator FLSpec the whole filter attributes is bypassed.

To Reproduce
Steps to reproduce the behavior:

1. Create workflow
2. Create step for collaborators
   self.next(
   self.col_step,
   foreach="collaborators",
   exclude=["attribute_not_in_collaborator", "attribute_in_collaborator"],
   )
3. The collaborator will still have "attribute_in_collaborator" because it doesn't have "attribute_not_in_collaborator"

Expected behavior
Either any attributes in the list that are in the collaborator FLSpec should be filtered or an error should be raised informing that " they are trying to delete attributes not in the collaborator FLSpec"

Screenshots
if exclude or include [0] not in clone no attributes are filtered

Desktop (please complete the following information):
Ubuntu 18.4