Update Rust crate serial_test to v3.2.0

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
serial_test	dev-dependencies	minor	3.1.1 -> 3.2.0

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Release Notes

palfrey/serial_test (serial_test)

### [`v3.2.0`](https://redirect.github.com/palfrey/serial_test/releases/tag/v3.2.0) [Compare Source](https://redirect.github.com/palfrey/serial_test/compare/v3.1.1...v3.2.0) #### What's Changed - Stop using tokio in test which runs all futures sync by [@​pgerber](https://redirect.github.com/pgerber) in [https://github.com/palfrey/serial_test/pull/114](https://redirect.github.com/palfrey/serial_test/pull/114) - Add `is_locked_serially()` to check if we are in a `#[serial]` context by [@​pgerber](https://redirect.github.com/pgerber) in [https://github.com/palfrey/serial_test/pull/113](https://redirect.github.com/palfrey/serial_test/pull/113) - CI step with fully updated dependencies by [@​palfrey](https://redirect.github.com/palfrey) and [@​vsirivol](https://redirect.github.com/vsirivol) in [https://github.com/palfrey/serial_test/pull/118](https://redirect.github.com/palfrey/serial_test/pull/118) - `default_features` -> `default-features` by [@​palfrey](https://redirect.github.com/palfrey) in [https://github.com/palfrey/serial_test/pull/119](https://redirect.github.com/palfrey/serial_test/pull/119) - Strip down the required features for various libraries by [@​palfrey](https://redirect.github.com/palfrey) in [https://github.com/palfrey/serial_test/pull/120](https://redirect.github.com/palfrey/serial_test/pull/120) #### New Contributors - [@​pgerber](https://redirect.github.com/pgerber) made their first contribution in [https://github.com/palfrey/serial_test/pull/114](https://redirect.github.com/palfrey/serial_test/pull/114) - [@​vsirivol](https://redirect.github.com/vsirivol) made their first contribution in [https://github.com/palfrey/serial_test/pull/118](https://redirect.github.com/palfrey/serial_test/pull/118) **Full Changelog**: https://github.com/palfrey/serial_test/compare/v3.1.1...v3.2.0

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