chore(deps): update actions-rust-lang/setup-rust-toolchain action to v1.9.0

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
actions-rust-lang/setup-rust-toolchain	action	minor	v1.8.0 -> v1.9.0

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Release Notes

actions-rust-lang/setup-rust-toolchain (actions-rust-lang/setup-rust-toolchain)

### [`v1.9.0`](https://togithub.com/actions-rust-lang/setup-rust-toolchain/releases/tag/v1.9.0) [Compare Source](https://togithub.com/actions-rust-lang/setup-rust-toolchain/compare/v1.8.0...v1.9.0) - Add extra argument `cache-on-failure` and forward it to `Swatinem/rust-cache`. ([#​39](https://togithub.com/actions-rust-lang/setup-rust-toolchain/issues/39) by [@​samuelhnrq](https://togithub.com/samuelhnrq))\ Set the default the value to true. This will result in more caching than previously. This helps when large dependencies are compiled only for testing to fail.

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