### Godot version

3fa8fad

### System information

Debian Linux x86

### Issue description

#79205 introduces a regression to the way rpc configs are inherited, causing this error:

```
ERROR: Unable to get the RPC configuration for the function "foo" at path: "/root/Node". This happens when the method is missing or not marked for RPCs in the local script.
```

even though the function exists both in the server and the client. If you `print(self.foo)`, it even tells you that it's rpc: `Node(client.gd)::foo (rpc)` 

Before #79205 `GdScriptCompiler::_populate_class_members` used `GDScriptCache::get_full_script` to access the base script. This causes the parent script to be compiled (if it is not compiled yet), which in turn initializes the `rpc_config` property with a copy of the base value in [gdscript.cpp::_init_rpc_methods_properties](https://github.com/godotengine/godot/blob/3fa8fad26b97a8af20e7996b7e17d8f23fc04b89/modules/gdscript/gdscript.cpp#L1398-L1412)

However, `GDScriptCache::get_shallow_script` does not compile and thus does not initialize the `rpc_config` of the base script, causing the rpc functions not being included in the rpc config.

### Steps to reproduce

Extend a gdscript with a `@rpc` function annotation and try to do a network call:

server.gd:
```gdscript
extends Node

func _ready():
	var peer := ENetMultiplayerPeer.new()
	peer.create_server(1337)
	multiplayer.multiplayer_peer = peer

@rpc("any_peer") func foo():
	print("Server")
```

parent.gd:
```gdscript
extends Node

@rpc func foo(): pass
```

client.gd:
```gdscript
extends "parent.gd"

func _ready():
	var peer := ENetMultiplayerPeer.new()
	peer.create_client("localhost", 1337)
	multiplayer.connected_to_server.connect(func (): self.foo.rpc_id(1))
	multiplayer.multiplayer_peer = peer
```


### Minimal reproduction project

[test.zip](https://github.com/godotengine/godot/files/12215814/test.zip)

Object *obj = p_variant;
	if (obj == nullptr || obj->get_instance_id().is_null()) {
		return nullptr;
	}
	return Object::cast_to<GDScript>(obj);
}
void GDScript::_get_dependencies(RBSet<GDScript *> &p_dependencies, const GDScript *p_except) {
	if (p_dependencies.has(this)) {
		return;
	}
	p_dependencies.insert(this);
	for (const KeyValue<StringName, GDScriptFunction *> &E : member_functions) {
		if (E.value == nullptr) {
			continue;
		}
		for (const Variant &V : E.value->constants) {
			GDScript *scr = _get_gdscript_from_variant(V);
			if (scr != nullptr && scr != p_except) {
				scr->_get_dependencies(p_dependencies, p_except);
			}
		}
	}
	if (implicit_initializer) {
		for (const Variant &V : implicit_initializer->constants) {
			GDScript *scr = _get_gdscript_from_variant(V);
			if (scr != nullptr && scr != p_except) {
				scr->_get_dependencies(p_dependencies, p_except);
			}
		}