### 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)

method_info.flags |= METHOD_FLAG_STATIC;
	}
	codegen.generator->write_start(p_script, func_name, is_static, rpc_config, return_type);
	int optional_parameters = 0;
	if (p_func) {
		for (int i = 0; i < p_func->parameters.size(); i++) {
			const GDScriptParser::ParameterNode *parameter = p_func->parameters[i];
			GDScriptDataType par_type = _gdtype_from_datatype(parameter->get_datatype(), p_script);
			uint32_t par_addr = codegen.generator->add_parameter(parameter->identifier->name, parameter->initializer != nullptr, par_type);
			codegen.parameters[parameter->identifier->name] = GDScriptCodeGenerator::Address(GDScriptCodeGenerator::Address::FUNCTION_PARAMETER, par_addr, par_type);
			method_info.arguments.push_back(parameter->get_datatype().to_property_info(parameter->identifier->name));
			if (parameter->initializer != nullptr) {
				optional_parameters++;
			}
		}
		method_info.default_arguments.append_array(p_func->default_arg_values);
	}
	
	bool is_implicit_initializer = !p_for_ready && !p_func && !p_for_lambda;
	bool is_initializer = p_func && !p_for_lambda && p_func->identifier->name == GDScriptLanguage::get_singleton()->strings._init;
	bool is_implicit_ready = !p_func && p_for_ready;
	if (!p_for_lambda && is_implicit_initializer) {
		
		
		
		for (const GDScriptParser::ClassNode::Member &member : p_class->members) {
			if (member.type != GDScriptParser::ClassNode::Member::VARIABLE) {
				continue;
			}
			const GDScriptParser::VariableNode *field = member.variable;