Auto merge of #132854 - RalfJung:query-key-limit, r=compiler-errors

query/plumbing: adjust comment to reality

The limit for the query key size got changed recently in f51ec110a7 but the comment was not updated.

Though maybe it is time to intern `CanonicalTypeOpAscribeUserTypeGoal` rather than copying it everywhere?

r? `@lcnr`

compiler/rustc_middle/src/query/plumbing.rs

@@ -319,7 +319,7 @@ pub fn provided_to_erased<'tcx>(
 
                 pub type Storage<'tcx> = <$($K)* as keys::Key>::Cache<Erase<$V>>;
 
-                // Ensure that keys grow no larger than 72 bytes by accident.
+                // Ensure that keys grow no larger than 80 bytes by accident.
                 // Increase this limit if necessary, but do try to keep the size low if possible
                 #[cfg(target_pointer_width = "64")]
                 const _: () = {