Update GraceDB calls and files to those available in O4

There are numerous extra unnecessary GraceDB calls that should be removed:

• Grabbing preferred event separately, when that could be done by using the superevent (superevent['preferred_event_data'])
• Grabbing every GW event instead of using provided neighbors/table in superevent
• Grabbing the sky map several times instead of once and passing along

Also data products that should be updated to be what we expect in O4:

• Combined sky map should be made using current tools in gwcelery, which would make them multiordered
• cWB and Burst sky maps should be multiordered when possible
• Ensure all pipelines that could appear in O4 are present and have the proper citations
• The VOEvent examples should be updated with new fields when applipical

changed milestone to %O4

added O4 label

assigned to @brandon.piotrzkowski

changed the description

mentioned in merge request !117 (merged)

marked the checklist item Grabbing preferred event separately, when that could be done by using the superevent (superevent['preferred_event_data']) as completed

marked the checklist item Grabbing every GW event instead of using provided neighbors/table in superevent as completed

marked the checklist item Combined sky map should be made using current tools in gwcelery, which would make them multiordered as completed

marked the checklist item cWB and Burst sky maps should be multiordered when possible as completed

changed the description

closed with commit b12c609a

closed with merge request !117 (merged)