This patch fixes an issue where the `CancellationToken::run_until_cancelled` never cancels the `Future` that returns `Ready` at the first `poll`.
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Co-authored-by: Luca BRUNO <lucab@lucabruno.net>
* sync: move CancellationToken to tokio-util
The `CancellationToken` utility is only available with the
`tokio_unstable` flag. This was done as the API is not final, but it
adds friction for users.
This patch moves `CancellationToken` to tokio-util where it is generally
available. The tokio-util crate does not have any constraints on
breaking change releases.
* fix clippy
* clippy again
