Bump which from 5.0.0 to 6.0.0

Bumps [which](https://github.com/harryfei/which-rs) from 5.0.0 to 6.0.0.
- [Release notes](https://github.com/harryfei/which-rs/releases)
- [Changelog](https://github.com/harryfei/which-rs/blob/master/CHANGELOG.md)
- [Commits](harryfei/which-rs@5.0.0...6.0.0)

---
updated-dependencies:
- dependency-name: which
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Cargo.toml

@@ -59,15 +59,15 @@ pager         = "0.16.1"
 procfs        = "0.16.0"
 regex         = "1.10"
 uzers         = "0.11"
-which         = "5"
+which         = "6"
 
 [target.'cfg(target_os = "macos")'.dependencies]
 libproc       = "0.14"
 nix           = {version = "0.27.1", features = ["process"]}
 errno         = "0.3"
 pager         = "0.16"
 uzers         = "0.11"
-which         = "5"
+which         = "6"
 
 [target.'cfg(target_os = "windows")'.dependencies]
 winapi        = { version = "0.3", features = ["handleapi", "minwindef", "psapi", "securitybaseapi", "tlhelp32", "winbase", "winnt", "iphlpapi"] }
@@ -77,7 +77,7 @@ bsd-kvm       = "0.1.5"
 bsd-kvm-sys   = "0.2.0"
 pager         = "0.16.1"
 uzers         = "0.11"
-which         = "5"
+which         = "6"
 
 [package.metadata.rpm.cargo]
 buildflags = ["--release"]