Rustdoc syntax highlighting for non-Rust code

Hello,

I would like to highlight some code not written in Rust (gdscript to be precise) in my crate's documentation, like this:

```gdscript
var some_var = 1
```

However it seems to me that rustdoc only highlight rust code: I tried c, cpp, python, lua and gdscript, and all render the same as text. Is there a way to make syntax highlighting work for non-Rust code ?

For precision I am on stable 1.48, and I build the documentation using cargo doc