[cargo] Update Rust crate rstest to 0.21.0

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
rstest	dev-dependencies	minor	0.19.0 -> 0.21.0

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Release Notes

la10736/rstest (rstest)

### [`v0.21.0`](https://togithub.com/la10736/rstest/blob/HEAD/CHANGELOG.md#0210-202461) [Compare Source](https://togithub.com/la10736/rstest/compare/v0.20.0...v0.21.0) ##### Changed - Add feature `crate-name` enabled by default to opt-in crate rename support. See [#​258](https://togithub.com/la10736/rstest/issues/258) ### [`v0.20.0`](https://togithub.com/la10736/rstest/blob/HEAD/CHANGELOG.md#0200-2024530) [Compare Source](https://togithub.com/la10736/rstest/compare/v0.19.0...v0.20.0) ##### Add - Implemented `#[by_ref]` attribute to take get a local lifetime for test arguments. See [#​241](https://togithub.com/la10736/rstest/issues/241) for more details. Thanks to [@​narpfel](https://togithub.com/narpfel) for suggesting it and useful discussions. - Support for import `rstest` with another name. See [#​221](https://togithub.com/la10736/rstest/issues/221) ##### Fixed - Don't remove Lifetimes from test function if any. See [#​230](https://togithub.com/la10736/rstest/issues/230) [#​241](https://togithub.com/la10736/rstest/issues/241) for more details. - [`PathBuf`](https://doc.rust-lang.org/std/path/struct.PathBuf.html) does no longer need to be in scope when using `#[files]` (see [#​242](https://togithub.com/la10736/rstest/pull/242)) - `#[from(now::accept::also::path::for::fixture)]` See [#​246](https://togithub.com/la10736/rstest/issues/246) for more details

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Configuration

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[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 82.65%. Comparing base (10ea73b) to head (c876665).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #61 +/- ## ======================================= Coverage 82.65% 82.65% ======================================= Files 7 7 Lines 3176 3176 ======================================= Hits 2625 2625 Misses 551 551 ```

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