chore(deps): update rust crate which to v6

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
which	dependencies	major	5.0.0 -> 6.0.0

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Release Notes

harryfei/which-rs (which)

### [`v6.0.0`](https://togithub.com/harryfei/which-rs/blob/HEAD/CHANGELOG.md#600) [Compare Source](https://togithub.com/harryfei/which-rs/compare/5.0.0...6.0.0) - MSRV is now 1.70 - Upgraded all dependencies to latest version

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