change a structure creation because of an API change

The change is that currently a work record has something like this data:

funder: [
    "10.1234/1234",
    "10.1234/1456"
]

Whereas now it has:

funder: [
  {DOI: "10.1234/1234",
    name: "National Science Foundation",
    award: [
      "award-1",
      "award-2"
     ]
   }
]
add facet filters only when there are any

this removes one extra “,” from API calls w/o facet filters