Rollup merge of #134045 - ehuss:triagebot-path-fixes, r=compiler-errors

Fix some triagebot mentions paths

This fixes some mentions paths in `triagebot.toml` that are no longer valid.

* rustdoc themes were merged into rustdoc.css (which already has a mention, and unfortunately can't independently mention the ayu theme). rust-lang/rust#115829 cc `@GuillaumeGomez` `@Cldfire`
* The entry for `inspect_obligations.rs` was never correct, from rust-lang/rust#122385. cc `@lcnr` `@compiler-errors`
* The entry for `need_type_info.rs` was moved in rust-lang/rust#127501

Author: matthiaskrgr