[3.x] Unclear instructions on how compiled export templates are named and should be renamed for install in `templates` directory

### Tested versions

Godot: 3.5.3
FreeBSD: 14.1

### System information

FreeBSD 14.1, Godot 3.5.3

### Issue description

I’m trying to build the export template for FreeBSD, but can’t get the files being generated. I’m using the steps documented [here](https://docs.godotengine.org/en/3.5/development/compiling/compiling_for_x11.html#building-export-templates). However, no files called `linux_x11_64_release` or `linux_x11_64_debug` are generated. What’s the issue? Or am I misunderstanding something?

Greetings,
Fabiano

PS: Specifying `module_webm_enabled=no` was necessary to build without an error I will deal with in a separate thread as soon as this issue is resolved!

### Steps to reproduce

```
git clone https://github.com/godotengine/godot.git
cd godot
git checkout 3.5.3-stable
scons platform=x11 module_webm_enabled=no
scons module_webm_enabled=no plaform=x11 tools=no target=release bits=64
scons module_webm_enabled=no plaform=x11 tools=no target=release_debug bits=64
find . -type f -name linux_x11_64_release
[nothing here]
```

### Minimal reproduction project (MRP)

This is not project-specific