Fix the version of mach2 in Cargo.toml (#8615)

The toml file specifies version `0.4.1` instead of `0.4.2`.

Using version `0.4.1` produces a compile error:

```
error[E0432]: unresolved import `mach2::ndr`
  --> external/crate_index__wasmtime-runtime-20.0.2/src/sys/unix/machports.rs:44:12
   |
44 | use mach2::ndr::*;
   |            ^^^ could not find `ndr` in `mach2`
```

That's because `ndr` was added in version `0.4.2`.

Note that the lock file specifies version `0.4.2` which explains
why this error doesn't happen normally.

Cargo.toml

@@ -263,7 +263,7 @@ async-trait = "0.1.71"
 heck = "0.4"
 similar = "2.1.0"
 toml = "0.8.10"
-mach2 = "0.4.1"
+mach2 = "0.4.2"
 memfd = "0.6.2"
 memoffset = "0.9.0"
 psm = "0.1.11"