update gene annotation builds

[ahwagner]

Currently, all transcripts in DoCM are labeled as build 74 of ensembl genes. Is this reflective of the VEP annotations we're pulling? My understanding is that the API only hits the most recent build... e74.rest.ensembl.org isn't a thing, unfortunately. I suggest that we check that the coordinates of our existing variants in DoCM are correct in 84, and then update our tags accordingly.