Very simple. Just refuse to present the bill to HM Queen Elizabeth II. No royal assent, no law.
If Parliament doesn’t like it, they can hold a vote of no confidence followed by a general election.
I think your idea is already scripted out and the more likely scenario. Queen Elizabeth might ring up Johnson on when he’s coming by to present the bill....with him responding he’s having ice cream and cake. She’ll laugh, and that’ll be the end of this drama.