### 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)


bool list_resolved = false;
	
	
	if (p_for->list && p_for->list->type == GDScriptParser::Node::CALL) {
		GDScriptParser::CallNode *call = static_cast<GDScriptParser::CallNode *>(p_for->list);
		GDScriptParser::Node::Type callee_type = call->get_callee_type();
		if (callee_type == GDScriptParser::Node::IDENTIFIER) {
			GDScriptParser::IdentifierNode *callee = static_cast<GDScriptParser::IdentifierNode *>(call->callee);
			if (callee->name == "range") {
				list_resolved = true;
				if (call->arguments.size() < 1) {
					push_error(R"*(Invalid call for "range()" function. Expected at least 1 argument, none given.)*", call->callee);
				} else if (call->arguments.size() > 3) {
					push_error(vformat(R"*(Invalid call for "range()" function. Expected at most 3 arguments, %d given.)*", call->arguments.size()), call->callee);
				} else {
					
					bool can_reduce = true;
					Vector<Variant> args;
					args.resize(call->arguments.size());
					for (int i = 0; i < call->arguments.size(); i++) {
						GDScriptParser::ExpressionNode *argument = call->arguments[i];
						reduce_expression(argument);