Auto merge of rust-lang#84623 - jackh726:gats-incomplete, r=nikomatsakis

Make GATs no longer an incomplete feature

Blocked on ~rust-lang#84622~, ~rust-lang#82272~, ~rust-lang#76826~

r? `@nikomatsakis`

Author: bors

compiler/rustc_feature/src/active.rs

@@ -405,7 +405,7 @@ declare_features! (
     (active, in_band_lifetimes, "1.23.0", Some(44524), None),
 
     /// Allows associated types to be generic, e.g., `type Foo<T>;` (RFC 1598).
-    (incomplete, generic_associated_types, "1.23.0", Some(44265), None),
+    (active, generic_associated_types, "1.23.0", Some(44265), None),
 
     /// Allows defining `trait X = A + B;` alias items.
     (active, trait_alias, "1.24.0", Some(41517), None),

compiler/rustc_lint/src/builtin.rs

@@ -2315,7 +2315,7 @@ declare_lint! {
     /// ### Example
     ///
     /// ```rust
-    /// #![feature(generic_associated_types)]
+    /// #![feature(const_generics)]
     /// ```
     ///
     /// {{produces}}