Auto merge of #98914 - fee1-dead-contrib:min-deref-patterns, r=compiler-errors

Minimal implementation of implicit deref patterns for Strings

cc `@compiler-errors` `@BoxyUwU` https://github.com/rust-lang/lang-team/issues/88 #87121

~~I forgot to add a feature gate, will do so in a minute~~ Done

compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs

@@ -1729,7 +1729,7 @@ impl<'tcx> InferCtxtPrivExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                 ty::Bool => Some(0),
                 ty::Char => Some(1),
                 ty::Str => Some(2),
-                ty::Adt(def, _) if tcx.is_diagnostic_item(sym::String, def.did()) => Some(2),
+                ty::Adt(def, _) if Some(def.did()) == tcx.lang_items().string() => Some(2),
                 ty::Int(..)
                 | ty::Uint(..)
                 | ty::Float(..)