Auto merge of #63870 - estebank:async-fn-call, r=oli-obk

Suggest call fn ctor passed as arg to fn with type param bounds

_Reviewer note: the relevant changes are in the second commit, the first is simple and mechanical, but verbose._

When forgetting to call a fn in an argument position to an fn that has a generic bound:

```rust
async fn foo() {}

fn bar(f: impl Future<Output=()>) {}

fn main() {
    bar(foo); // <- should be `bar(foo());`
}
```

suggest calling it:

```
error[E0277]: the trait bound `fn() -> impl std::future::Future {foo}: std::future::Future` is not satisfied
  --> $DIR/async-fn-ctor-passed-as-arg-where-it-should-have-been-called.rs:9:5
   |
LL | fn bar(f: impl Future<Output=()>) {}
   | --------------------------------- required by `bar`
...
LL |     bar(foo);
   |     ^^^ the trait `std::future::Future` is not implemented for `fn() -> impl std::future::Future {foo}`
   |
   = help: it looks like you forgot to use parentheses to call the function: `foo()`
```

Fix #63100. Follow up to #63833 and #63337.

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