ices/71471.rs: fixed with errors

[github-actions]

Issue: rust-lang/rust#71471

#!B

=== stdout ===
=== stderr ===
error: expected `[`, found `B`
 --> /home/runner/work/glacier/glacier/ices/71471.rs:2:3
  |
2 | #!B
  |   ^ expected `[`

error: aborting due to previous error

==============

[Alexendoo]

rust-lang/rust#71372 got reverted, so this currently still ICEs on master, rust-lang/rust#71487 contains a fix and test for it though. I'll move this back to ices/ at a later date if that doesn't get merged in the meanwhile