MONGOID-4833 omit testing on ruby-head for now (#4725)
MONGOID-4833 omit testing on ruby-head for now (#4725)

Co-authored-by: Oleg Pudeyev <516b9783fca517eecbd1d064da2d165310b19759@users.noreply.github.com>

mongodb/mongoid,mongodb/mongoid,mongodb/mongoid