fix: rm relatedPortlets from mock entries.json

MyUW uPortal has been modified to always suppress related portlets -- all relatedPortlets arrays will in practice be empty. This change makes this so in the mock entries.json as well.

If the relatedPortlets feature should be raised again, it should probably identify related portlets by reference (fname?) rather than by value.

In the meantime, this makes the mock entries.json more wiedly for updating demo content.