taplo is very slow on MacOS

[mrobinson]

Taplo seems to have an issue on MacOS with processing speed. This is what I see when I run ./mach fmt

$ time ./mach fmt

real	0m19.056s
user	0m2.091s
sys	0m7.640s

If I comment out taplo formatting, I see:

$ time ./mach fmt

real	0m1.622s
user	0m1.320s
sys	0m0.145s

[nicoburns]

I suspect a filesystem issue: that's usually the cause of perf differences between linux and macos. I notice taplo-cli is using the glob crate which is known to be slow and suggests that its doing custom filesystem walking logic. I bet this could be sped up by converting it to use the walkdir/ignore crates.