No link to "send bound" problem

[carols10cents]

There's two spots in async_fn_everywhere that try to link to [sb], but there isn't a corresponding [sb]: https://.... definition. I would fix this myself, but I don't know where this should link to 😅

The spots:

• rust-project-goals/src/2024h2/async_fn_everywhere.md

  Line 34 in db56b08

  **Send bounds.** A number of key pieces in the async Rust ecosystem remain unstable or stalled in their development by the lack of language features and/or standard interop traits. For example, the widely used [tower](https://crates.io/crates/tower) crate hasn't yet released a 1.0 of its `Service` trait because they are blocked waiting on a solution to the ["send bound"][sb] problem.

• rust-project-goals/src/2024h2/async_fn_everywhere.md

  Line 109 in db56b08

  The goal for the year is to stabilize a solution to the ["send bound" problem][sb].

[lqd]

I think these links are about rust-lang/rfcs#3654

[traviscross]

Also: https://smallcultfollowing.com/babysteps/blog/2023/02/01/async-trait-send-bounds-part-1-intro/

[lqd]

That is indeed what the now open async project goal RFC links to, here.

Apparently this page has been rewritten for the RFC and this link has been fixed.

[nikomatsakis]

fixed I think

[nikomatsakis]

Wait, no, I fixed it in the RFC :)

[nikomatsakis]

I should probably just redirect that page to the RFC

[nikomatsakis]

done.