ices/77218.rs: fixed with errors

[github-actions]

Issue: rust-lang/rust#77218

pub struct Cache {
    data: Vec<i32>,
}

pub fn list_data(cache: &Cache, key: usize) {
    for reference in vec![1, 2, 3] {
        if /*let*/ Some(reference) = cache.data.get(key) {
            unimplemented!()
        }
    }
}

=== stdout ===
=== stderr ===
error[E0601]: `main` function not found in crate `77218`
  --> /home/runner/work/glacier/glacier/ices/77218.rs:1:1
   |
1  | / pub struct Cache {
2  | |     data: Vec<i32>,
3  | | }
4  | |
...  |
10 | |     }
11 | | }
   | |_^ consider adding a `main` function to `/home/runner/work/glacier/glacier/ices/77218.rs`

error[E0308]: mismatched types
 --> /home/runner/work/glacier/glacier/ices/77218.rs:7:20
  |
7 |         if /*let*/ Some(reference) = cache.data.get(key) {
  |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `bool`, found `()`
  |
help: you might have meant to use pattern matching
  |
7 |         if /*let*/ let Some(reference) = cache.data.get(key) {
  |                    ^^^

error: aborting due to 2 previous errors

Some errors have detailed explanations: E0308, E0601.
For more information about an error, try `rustc --explain E0308`.
==============