Auto merge of rust-lang#85305 - MarcusDunn:master, r=pnkfelix

Stabilize bindings_after_at

attempting to stabilze bindings_after_at [rust-lang#65490](rust-lang#65490), im pretty new to the whole thing so any pointers are greatly appreciated.

Author: bors

alloc/src/lib.rs

@@ -85,6 +85,7 @@
 #![feature(allow_internal_unstable)]
 #![feature(arbitrary_self_types)]
 #![feature(async_stream)]
+#![cfg_attr(bootstrap, feature(bindings_after_at))]
 #![feature(box_patterns)]
 #![feature(box_syntax)]
 #![feature(cfg_sanitize)]
@@ -145,7 +146,6 @@
 #![feature(associated_type_bounds)]
 #![feature(slice_group_by)]
 #![feature(decl_macro)]
-#![feature(bindings_after_at)]
 // Allow testing this library
 
 #[cfg(test)]