### 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)


}
					if (setter_function == nullptr) {
						push_error(vformat(R"(Setter "%s" not found.)", member.variable->setter_pointer->name), member.variable);
					} else if (setter_function->parameters.size() != 1) {
						push_error(vformat(R"(Function "%s" cannot be used as setter because of its signature.)", setter_function->identifier->name), member.variable);
					} else if (!is_type_compatible(member.variable->datatype, setter_function->parameters[0]->datatype, true)) {
						push_error(vformat(R"(Function with argument type "%s" cannot be used as setter for a property of type "%s".)", setter_function->parameters[0]->datatype.to_string(), member.variable->datatype.to_string()), member.variable);
					} else {
						has_valid_setter = true;
#ifdef DEBUG_ENABLED
						if (member.variable->datatype.builtin_type == Variant::FLOAT && setter_function->parameters[0]->datatype.builtin_type == Variant::INT) {
							parser->push_warning(member.variable, GDScriptWarning::NARROWING_CONVERSION);
						}
#endif
					}
				}
				if (member.variable->datatype.is_variant() && has_valid_getter && has_valid_setter) {
					if (!is_type_compatible(getter_function->datatype, setter_function->parameters[0]->datatype, true)) {
						push_error(vformat(R"(Getter with type "%s" cannot be used along with setter of type "%s".)", getter_function->datatype.to_string(), setter_function->parameters[0]->datatype.to_string()), member.variable);
					}
				}
			}
#ifdef DEBUG_ENABLED
			parser->ignored_warnings = previously_ignored_warnings;
#endif 
		}
	}
	parser->current_class = previous_class;
}
void GDScriptAnalyzer::resolve_class_body(GDScriptParser::ClassNode *p_class, bool p_recursive) {