Fixed nighly build of wasm-bindgen-futures

[daxpedda]

The nightly features stdsimd was recently just split into multiple features.
Specifically we now need the stdarch_wasm_atomic_wait feature for the atomics target.

See rust-lang/rust#117372.

[fzyzcjy]

Looks like this is related to fzyzcjy/flutter_rust_bridge#1727. Thanks for fixing!

P.S. Error I saw:

error[E0658]: use of unstable library feature 'stdarch_wasm_atomic_wait'
  --> /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/wasm-bindgen-futures-0.4.39/src/task/multithread.rs:38:13
   |
38 |             core::arch::wasm32::memory_atomic_notify(
   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: see issue #77839 <https://github.com/rust-lang/rust/issues/77839> for more information
   = help: add `#![feature(stdarch_wasm_atomic_wait)]` to the crate attributes to enable
   = note: this compiler was built on 2024-02-05; consider upgrading it if it is out of date

error[E0635]: unknown feature `stdsimd`
  --> /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/wasm-bindgen-futures-0.4.39/src/lib.rs:33:49
   |
33 | #![cfg_attr(target_feature = "atomics", feature(stdsimd))]
   |                                                 ^^^^^^^

Some errors have detailed explanations: E0635, E0658.
For more information about an error, try `rustc --explain E0635`.
error: could not compile `wasm-bindgen-futures` (lib) due to 2 previous errors
warning: build failed, waiting for other jobs to finish...

[fzyzcjy]

Related: #3830