ices/86800.rs: fixed with errors

[github-actions]

Issue: rust-lang/rust#86800

#![feature(type_alias_impl_trait)]

use std::future::Future;

struct Connection {}

trait Transaction {}

struct TestTransaction<'conn> {
    conn: &'conn Connection,
}

impl<'conn> Transaction for TestTransaction<'conn> {}

struct Context {}

type TransactionResult<O> = Result<O, ()>;

type TransactionFuture<'__, O> = impl '__ + Future<Output = TransactionResult<O>>;

fn execute_transaction_fut<'f, F, O>(
    f: F,
) -> impl FnOnce(&mut dyn Transaction) -> TransactionFuture<O>
where
    F: FnOnce(&mut dyn Transaction) -> TransactionFuture<O> + 'f,
{
    f
}

impl Context {
    async fn do_transaction<O>(
        &self,
        f: impl FnOnce(&mut dyn Transaction) -> TransactionFuture<O>,
    ) -> TransactionResult<O> {
        let mut conn = Connection {};
        let mut transaction = TestTransaction { conn: &mut conn };
        f(&mut transaction).await
    }
}

=== stdout ===
=== stderr ===
error[E0601]: `main` function not found in crate `86800`
  --> /home/runner/work/glacier/glacier/ices/86800.rs:39:2
   |
39 | }
   |  ^ consider adding a `main` function to `/home/runner/work/glacier/glacier/ices/86800.rs`

error: unconstrained opaque type
  --> /home/runner/work/glacier/glacier/ices/86800.rs:19:34
   |
19 | type TransactionFuture<'__, O> = impl '__ + Future<Output = TransactionResult<O>>;
   |                                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: `TransactionFuture` must be used in combination with a concrete type within the same module

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0601`.
==============