fix: [torrust#691] unknown feature stdsimd

```
error[E0635]: unknown feature `stdsimd`
  --> /home/josecelano/.cargo/registry/src/index.crates.io-6f17d22bba15001f/ahash-0.7.7/src/lib.rs:33:42
   |
33 | #![cfg_attr(feature = "stdsimd", feature(stdsimd))]
   |                                          ^^^^^^^

   Compiling aho-corasick v1.1.2
For more information about this error, try `rustc --explain E0635`.
error: could not compile `ahash` (lib) due to 1 previous error
warning: build failed, waiting for other jobs to finish...
```

With:

```
nightly-x86_64-unknown-linux-gnu (default)
rustc 1.78.0-nightly (98aa3624b 2024-02-08)
``

Author: josecelano