Update Rust crate rstest to 0.19

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
rstest	dev-dependencies	minor	0.18 -> 0.19

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Release Notes

la10736/rstest (rstest)

### [`v0.19.0`](https://togithub.com/la10736/rstest/blob/HEAD/CHANGELOG.md#0190-202449) [Compare Source](https://togithub.com/la10736/rstest/compare/v0.18.2...v0.19.0) ##### Changed - Defined `rust-version` for each crate (see [#​227](https://togithub.com/la10736/rstest/issues/227)) ##### Fixed - `#[once]` fixtures now require the returned type to be [`Sync`](https://doc.rust-lang.org/std/marker/trait.Sync.html) to prevent UB when tests are executed in parallel. (see [#​235](https://togithub.com/la10736/rstest/issues/235) for more details) - `#[future(awt)]` and `#[awt]` now properly handle mutable (`mut`) parameters by treating futures as immutable and treating the awaited rebinding as mutable.

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Configuration

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