E0529 needs to be updated to new format

[sophiajt]

From: src/test/compile-fail/E0529.rs

E0529 needs a span_label, updating it from:

error[E0529]: expected an array or slice, found `f32`
  --> src/test/compile-fail/E0529.rs:16:9
   |
16 |         [a, b] => { //~ ERROR E0529
   |         ^^^^^^

To:

error[E0529]: expected an array or slice, found `f32`
  --> src/test/compile-fail/E0529.rs:16:9
   |
16 |         [a, b] => { //~ ERROR E0529
   |         ^^^^^^ pattern cannot match `f32` type
``