### Godot version

4.1.beta3

### System information

Fedora Workstation 38 - Godot 4.1.beta3 - Vulkan (Forward+)

### Issue description

**This is an issue created by the production team, we're working on it**

Currently, it's impossible to call virtual functions within GDScript.

This currently returns an error:
```gdscript
# a.gd
extends Node

func _process(delta: float) -> void:
	pass
```

```gdscript
# main.gd
extends Node

var my_node: Node = preload("res://a.gd").new()

func _process(delta: float) -> void:
	my_node._process(delta)  # Cannot call virtual function "_process()" because it hasn't been defined.
```

### Steps to reproduce

1. Create a script (`a.gd`) based on `Node` that declares `_process()`;
2. Create a main node;
3. Attach a script to the main node;
4. Initialize a variable with a new `a.gd` instance;
5. Try to run `_process()` on that node;
6. Find out that it returns an error.

### Minimal reproduction project

[virtual_functions.zip (updated)](https://github.com/godotengine/godot/files/11823992/virtual_functions.zip)


}
		}
		
		for (const KeyValue<int, GDScriptParser::ArrayNode *> &E : arrays) {
			int index = E.key;
			if (index < par_types.size() && par_types[index].has_container_element_type()) {
				update_array_literal_element_type(E.value, par_types[index].get_container_element_type());
			}
		}
		validate_call_arg(par_types, default_arg_count, method_flags.has_flag(METHOD_FLAG_VARARG), p_call);
		if (base_type.kind == GDScriptParser::DataType::ENUM && base_type.is_meta_type) {
			
			base_type.is_meta_type = false;
		}
		if (is_self && static_context && !method_flags.has_flag(METHOD_FLAG_STATIC)) {
			if (parser->current_function) {
				
				GDScriptParser::FunctionNode *parent_function = parser->current_function;
				while (parent_function->source_lambda) {
					parent_function = parent_function->source_lambda->parent_function;
				}
				push_error(vformat(R"*(Cannot call non-static function "%s()" from static function "%s()".)*", p_call->function_name, parent_function->identifier->name), p_call);
			} else {
				push_error(vformat(R"*(Cannot call non-static function "%s()" for static variable initializer.)*", p_call->function_name), p_call);
			}
		} else if (!is_self && base_type.is_meta_type && !method_flags.has_flag(METHOD_FLAG_STATIC)) {
			base_type.is_meta_type = false; 
			push_error(vformat(R"*(Cannot call non-static function "%s()" on the class "%s" directly. Make an instance instead.)*", p_call->function_name, base_type.to_string()), p_call);
		} else if (is_self && !method_flags.has_flag(METHOD_FLAG_STATIC)) {
			mark_lambda_use_self();