Create Collection - if "Use metadata fields from [Parent]" is checked, send blocknames & input levels as undefined

[g-saracca]

As discussed with @pdurbin and @GPortas, we should not send metadata block names & input levels from the create collection form if "Use metadata fields from [Parent]" is checked.
Instead we should send those two properties as undefined. Before we were sending the metadata blocks and input levels that were configured in the parent collection.

[pdurbin]

Yes, thanks. That way if the parent changes in the future, the child is not frozen in time. The child will inherit the updated metadata blocks from the parent.