Bump nix from 0.28.0 to 0.29.0

Bumps [nix](https://github.com/nix-rust/nix) from 0.28.0 to 0.29.0.
- [Changelog](https://github.com/nix-rust/nix/blob/master/CHANGELOG.md)
- [Commits](nix-rust/nix@v0.28.0...v0.29.0)

---
updated-dependencies:
- dependency-name: nix
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Cargo.toml

@@ -30,7 +30,7 @@ dirs = "5.0"
 env_logger = { version = "0.10", default-features = false }
 log = { workspace = true }
 logging_timer = "1.1"
-nix = { version = "0.28", features = ["process"] }
+nix = { version = "0.29", features = ["process"] }
 serde = { version = "1.0", features = ["derive"] }
 tempfile = { workspace = true }
 toml = "0.8"