Rust: Clippy performance status update

If you know anything about me, is probably that I make Clippy as fast as I can. I love making programs faster both because (a) it&rsquo;s a puzzle, because (b) I don&rsquo;t think that we should expect users to have access to high-end hardware in order to compile a program and because (c) the energy footprint is smaller, which satisfies my ideological fight against waste. So some time after I…