Auto merge of #103426 - matthiaskrgr:rollup-n6dqdy8, r=matthiaskrgr

Rollup of 9 pull requests

Successful merges:

 - #103123 (Introduce `subst_iter` and `subst_iter_copied` on `EarlyBinder` )
 - #103328 (Do not suggest trivially false const predicates)
 - #103354 (Escape string literals when fixing overlong char literal)
 - #103355 (Handle return-position `impl Trait` in traits properly in `register_hidden_type`)
 - #103368 (Delay ambiguity span bug in normalize query iff not rustdoc)
 - #103388 (rustdoc: remove unused CSS class `.result-description`)
 - #103399 (Change `unknown_lint` applicability to `MaybeIncorrect`)
 - #103401 (Use functions for headings rustdoc GUI test)
 - #103412 (Fix typo in docs of `String::leak`.)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup