ices/92893.rs: fixed with errors

[github-actions]

Issue: rust-lang/rust#92893

struct Bug<A = [(); (let a = (), 1).1]> {
    a: A   
}

fn main() {}

=== stdout ===
=== stderr ===
error: `let` expressions are not supported here
 --> /home/runner/work/glacier/glacier/ices/92893.rs:1:22
  |
1 | struct Bug<A = [(); (let a = (), 1).1]> {
  |                      ^^^^^^^^^^
  |
  = note: only supported directly in conditions of `if` and `while` expressions

error[E0658]: `let` expressions in this position are unstable
 --> /home/runner/work/glacier/glacier/ices/92893.rs:1:22
  |
1 | struct Bug<A = [(); (let a = (), 1).1]> {
  |                      ^^^^^^^^^^
  |
  = note: see issue #53667 <https://github.com/rust-lang/rust/issues/53667> for more information
  = help: add `#![feature(let_chains)]` to the crate attributes to enable

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0658`.
==============