E0282 needs to be updated to new format

[sophiajt]

From: src/test/compile-fail/issue-23041.rs

Error E0282 needs a span_label, a note, and an updated title, updating it from:

error[E0282]: unable to infer enough type information about `_`; type annotations or generic parameter binding required
  --> src/test/compile-fail/issue-23041.rs:16:22
   |
16 |     b.downcast_ref::<fn(_)->_>(); //~ ERROR E0282
   |                      ^^^^^^^^

To:

error[E0282]: unable to infer enough type information about `_` 
  --> src/test/compile-fail/issue-23041.rs:16:22
   |
16 |     b.downcast_ref::<fn(_)->_>(); //~ ERROR E0282
   |                      ^^^^^^^^ cannot infer type for `_`
   |
   = note: type annotations or generic parameter binding required

[medzin]

I will do it.

[sophiajt]

I must have been asleep when I wrote the label. Updated it so it reads better. Sorry about that :)