PCK could leak source code

**Your Godot version:**
v4.3.stable

**Issue description:**
[This documentation page](https://docs.godotengine.org/en/stable/tutorials/export/exporting_pcks.html#:~:text=no%20source%20code%20disclosure%20needed%20for%20mods) says that when using PCK resource packs for mods or texture packs, it won't **disclose the source code**, but if a user puts a script in the PCK, it can get access and read all of the scripts. This can be dangerous for public releases of games or apps.

It would be a good idea to allow the dev **choose what gets imported** with `ProjectSettings.load_resource_pack()` (like textures or sounds) and avoid loading custom scripts.

**URL to the documentation page:**
https://docs.godotengine.org/en/stable/tutorials/export/exporting_pcks.html#

If you know how to fix the issue you are reporting please
consider opening a pull request. We provide a tutorial on
using git here: https://docs.godotengine.org/en/stable/community/contributing/pr_workflow.html,
writing documentation at https://docs.godotengine.org/en/stable/community/contributing/docs_writing_guidelines.html
and contributing to the class reference here: https://docs.godotengine.org/en/stable/community/contributing/updating_the_class_reference.html