Auto merge of #111224 - jyn514:default-tidy, r=pietroalbini

Remove `tidy` key in PR CI

This avoids confusing error messages when adding an `auto` job to CI (as recommended in the dev-guide: https://rustc-dev-guide.rust-lang.org/tests/ci.html#using-ci-to-test).

cc https://rust-lang.zulipchat.com/#narrow/stream/182449-t-compiler.2Fhelp/topic/Do.20.60needs-profiler-support.60.20tests.20not.20run.20in.20CI.3F/near/355302998

r? `@ghost`

Author: bors