async_yields_async with tokio: compile denied by clippy but rustc ok, probably not ICE but false positive

Summary

error: an async construct yields a type which is itself awaitable

let server_thread_handle = tokio::task::spawn(async move {
                loop {
                    /* doing something blocking */
                }
                ^ awaitable value not awaited
            });
| |_________- outer async construct
thread_handles.push(server_thread_handle);

   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#async_yields_async
   = note: `#[deny(clippy::async_yields_async)]` on by default

Version

rustc 1.70.0-beta.5 (16ec1c0a8 2023-05-20)
binary: rustc
commit-hash: 16ec1c0a8092cf54bc59d0ea9b10d8b50aed42be
commit-date: 2023-05-20
host: x86_64-unknown-linux-gnu
release: 1.70.0-beta.5
LLVM version: 16.0.2

Error output

<backtrace>
error: an async construct yields a type which is itself awaitable

Start by reproducing the reported async_yields_async diagnostic with tokio using rustc 1.70.0-beta.5, then compare Clippy's result with rustc's accepted behavior. Done means the report has a minimal reproducible example and the lint's behavior is corrected or clearly documented.