Democrats will either have to jettison elements of the Biden agenda, or cram their entire legislative package into one bill.An advisory ruling from an obscure Washington official last week might complicate the Biden administration’s efforts to push trillions of dollars in new taxes and spending.Multiple news stories confirmed the opinion from the Senate parliamentarian, Elizabeth MacDonough, which was not released publicly. In sum, it presents Democrats a potentially difficult decision later this year: they will either have to jettison elements of the Biden agenda, or cram their entire legislative package into one bill—turning it into a “Christmas tree” that could...