### Godot version

4.1.3

### System information

Linux

### Issue description

I'm trying to make an editor plugin on Rust:

```rust
#[derive(GodotClass)]
#[class(tool, editor_plugin, init, base=EditorPlugin)]
pub struct MyEditorPluginBase {}
```

But due to some limitations, I still have to use GDScript for some specific things.

So I tried to make a subclass of this Rust class:

```gdscript
@tool
class_name MyEditorPlugin
extends MyEditorPluginBase
```

This would work if `MyEditorPluginBase` was a GDScript class, but since it's a GDExtension class in my case, it doesn't work:

> Unable to load addon script from path: 'res://addons/my_addon/my_editor_plugin.gd' Base type is not EditorPlugin.

But it obviously **IS** EditorPlugin!

![godot-editorplugin-docs](https://github.com/godotengine/godot/assets/3236464/4665deeb-30f0-45cd-bfff-56101b9d4875)

![godot-editorplugin](https://github.com/godotengine/godot/assets/3236464/b1b6ecb4-de22-4abd-91a3-e180691f67ee)

If I understand correctly, this behavior is caused by this function, which checks some mysterious "instance base type" instead of real inheritance:

https://github.com/godotengine/godot/blob/fa4a65387ea41506ecc519fc61a06da110dce51c/editor/editor_node.cpp#L3456-L3458

https://github.com/godotengine/godot/blob/fa4a65387ea41506ecc519fc61a06da110dce51c/modules/gdscript/gdscript.cpp#L260-L263

Since the [documentation](https://docs.godotengine.org/en/stable/tutorials/plugins/editor/making_plugins.html#the-script-file) doesn't say that the script must be a **direct** subclass of EditorPlugin (and an indirect subclass works fine in GDScript), I interpret this behavior as a Godot bug.

### Steps to reproduce

See above

### Minimal reproduction project

[gdext_editor_plugin_test.zip](https://github.com/godotengine/godot/files/13451014/gdext_editor_plugin_test.zip)
OS::get_singleton()->print("  --audio-output-latency <ms>       Override audio output latency in milliseconds (default is 15 ms).\n");
	OS::get_singleton()->print("                                    Lower values make sound playback more reactive but increase CPU usage, and may result in audio cracking if the CPU can't keep up.\n");
	OS::get_singleton()->print("  --rendering-method <renderer>     Renderer name. Requires driver support.\n");
	OS::get_singleton()->print("  --rendering-driver <driver>       Rendering driver (depends on display driver).\n");
	OS::get_singleton()->print("  --gpu-index <device_index>        Use a specific GPU (run with --verbose to get available device list).\n");
	OS::get_singleton()->print("  --text-driver <driver>            Text driver (Fonts, BiDi, shaping).\n");
	OS::get_singleton()->print("  --tablet-driver <driver>          Pen tablet input driver.\n");
	OS::get_singleton()->print("  --headless                        Enable headless mode (--display-driver headless --audio-driver Dummy). Useful for servers and with --script.\n");
	OS::get_singleton()->print("  --write-movie <file>              Writes a video to the specified path (usually with .avi or .png extension).\n");
	OS::get_singleton()->print("                                    --fixed-fps is forced when enabled, but it can be used to change movie FPS.\n");
	OS::get_singleton()->print("                                    --disable-vsync can speed up movie writing but makes interaction more difficult.\n");
	OS::get_singleton()->print("                                    --quit-after can be used to specify the number of frames to write.\n");
	OS::get_singleton()->print("\n");
	OS::get_singleton()->print("Display options:\n");
	OS::get_singleton()->print("  -f, --fullscreen                  Request fullscreen mode.\n");
	OS::get_singleton()->print("  -m, --maximized                   Request a maximized window.\n");
	OS::get_singleton()->print("  -w, --windowed                    Request windowed mode.\n");
	OS::get_singleton()->print("  -t, --always-on-top               Request an always-on-top window.\n");
	OS::get_singleton()->print("  --resolution <W>x<H>              Request window resolution.\n");
	OS::get_singleton()->print("  --position <X>,<Y>                Request window position (if set, screen argument is ignored).\n");
	OS::get_singleton()->print("  --screen <N>                      Request window screen.\n");
	OS::get_singleton()->print("  --single-window                   Use a single window (no separate subwindows).\n");
	OS::get_singleton()->print("  --xr-mode <mode>                  Select XR (Extended Reality) mode ['default', 'off', 'on'].\n");
	OS::get_singleton()->print("\n");
	OS::get_singleton()->print("Debug options:\n");
	OS::get_singleton()->print("  -d, --debug                       Debug (local stdout debugger).\n");
	OS::get_singleton()->print("  -b, --breakpoints                 Breakpoint list as source::line comma-separated pairs, no spaces (use %%20 instead).\n");
	OS::get_singleton()->print("  --profiling                       Enable profiling in the script debugger.\n");
	OS::get_singleton()->print("  --gpu-profile                     Show a GPU profile of the tasks that took the most time during frame rendering.\n");
	OS::get_singleton()->print("  --gpu-validation                  Enable graphics API validation layers for debugging.\n");