Performance issue for x test tidy

x test tidy now cost about 19s on my machine (a M2 mac), I think it's a little bit too long for a trivial fix like https://github.com/rust-lang/rust/pull/142871, when I discussed with @jieyouxu , he told me it only cost 9s on his dev environment(a WSL).

so I added some logs for cost time in each check in tidy test:
https://github.com/chenyukang/rust/blob/106a6d46375f7c13d4fee3511736193f59b74542/src/tools/tidy/src/main.rs#L87-L95

The result for each part is:

I also meet the issue of https://github.com/rust-lang/rust/issues/134648, but I do not know how to reproduce it now.

• Do we need to run every tidy check phase for all kind of changes, I guess we may improve on this
• Running them concurrently could speed things up https://github.com/rust-lang/rust/issues/141074
• I haven't got the reason why it's much slower on my dev compared to @jieyouxu 's dev, maybe network speed ?

Start by running x test tidy and inspect the timing instrumentation discussed for src/tools/tidy/src/main.rs lines 87–95. Compare the costs of each tidy check phase, investigate the environment difference described in the issue, and review issues 134648 and 141074. Done means the bottleneck and a concrete performance improvement are identified and verified.