Update Rust crate nix to 0.31.2 (#3114)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [nix](https://redirect.github.com/nix-rust/nix) |
workspace.dependencies | patch | `0.31.1` -> `0.31.2` |

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Author: nextest-bot

Cargo.toml

@@ -96,7 +96,7 @@ nextest-filtering = { version = "0.18.0", path = "nextest-filtering" }
 nextest-metadata = { version = "0.13.3", path = "nextest-metadata" }
 nextest-runner = { path = "nextest-runner" }
 nextest-workspace-hack = "0.1.0"
-nix = { version = "0.31.1", default-features = false, features = ["signal"] }
+nix = { version = "0.31.2", default-features = false, features = ["signal"] }
 num_threads = "0.1.7"
 # Note: we don't use owo-colors' if_supports_color support for now, instead preferring to use our
 # own supports-color + stylesheets everywhere.