Fix typo in const_generics replaced with adt_const_params note

Author: MingweiSamuel

compiler/rustc_feature/src/removed.rs

@@ -104,7 +104,7 @@ declare_features! (
     (removed, quote, "1.33.0", Some(29601), None, None),
     /// Allows const generic types (e.g. `struct Foo<const N: usize>(...);`).
     (removed, const_generics, "1.34.0", Some(44580), None,
-     Some("removed in favor of `#![feature(adt_const_params]` and `#![feature(generic_const_exprs)]`")),
+     Some("removed in favor of `#![feature(adt_const_params)]` and `#![feature(generic_const_exprs)]`")),
     /// Allows `[x; N]` where `x` is a constant (RFC 2203).
     (removed, const_in_array_repeat_expressions,  "1.37.0", Some(49147), None,
      Some("removed due to causing promotable bugs")),