Add `await_holding_invalid_type` lint
changelog: [`await_holding_invalid_type`]
This lint allows users to create a denylist of types which are not allowed to be
held across await points. This is essentially a re-implementation of the
language-level [`must_not_suspend`
lint](https://github.com/rust-lang/rust/issues/83310). That lint has a lot of
work still to be done before it will reach Rust stable, and in the meantime
there are a lot of types which can trip up developers if they are used
improperly.
I originally implemented this specifically for `tracing::span::Entered`, until I discovered #8434 and read the commentary on that PR. Given this implementation is fully user configurable, doesn't tie clippy to any one particular crate, and introduces no additional dependencies, it seems more appropriate.
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