ices/81899.rs: fixed with errors

[github-actions]

Issue: rust-lang/rust#81899

const _CONST: &[u8] = &f(&[], |_| {});

const fn f<F>(_: &[u8], _: F) -> &[u8]
where
    F: FnMut(&u8),
{
    panic!()
}

fn main() {}

=== stdout ===
=== stderr ===
error[E0277]: expected a `FnMut<(&u8,)>` closure, found `[closure@/home/runner/work/glacier/glacier/ices/81899.rs:1:31: 1:37]`
 --> /home/runner/work/glacier/glacier/ices/81899.rs:1:24
  |
1 | const _CONST: &[u8] = &f(&[], |_| {});
  |                        ^ expected an `FnMut<(&u8,)>` closure, found `[closure@/home/runner/work/glacier/glacier/ices/81899.rs:1:31: 1:37]`
2 | 
3 | const fn f<F>(_: &[u8], _: F) -> &[u8]
  |          - required by a bound in this
4 | where
5 |     F: FnMut(&u8),
  |        ---------- required by this bound in `f`
  |
  = help: the trait `for<'r> FnMut<(&'r u8,)>` is not implemented for `[closure@/home/runner/work/glacier/glacier/ices/81899.rs:1:31: 1:37]`

error: aborting due to previous error

For more information about this error, try `rustc --explain E0277`.
==============

[JohnTitor]

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