### Godot version

v4.0.3.stable.official [5222a99f5]
Master [6101240231600c871f5c5473872532c68ea3268c] (confirmed by https://github.com/godotengine/godot/issues/77666#issuecomment-1568952502)

### System information

Window 10

### Issue description

References are not unreferenced at the end of `if` scopes.

### Steps to reproduce

Copy, paste and run the snippet below, check the results:

```gdscript
extends Node


func _ready() -> void:
  var ref := RefCounted.new()
  var ref_count : int

  # OK
  ref_count = ref.get_reference_count()
  print('Expected: 1, Result: %d' % ref_count)

  # OK
  if true:
    var temp := ref
    temp = null

  ref_count = ref.get_reference_count()
  print('Expected: 1, Result: %d' % ref_count)

  # FAIL
  if true:
    var temp := ref

  ref_count = ref.get_reference_count()
  print('Expected: 1, Result: %d' % ref_count)
```

Output example:

```
Expected: 1, Result: 1
Expected: 1, Result: 1
Expected: 1, Result: 2
```

### Minimal reproduction project

N/A
#ifdef DEBUG_ENABLED
	if (this->_is_tool) {
		push_error(R"("@tool" annotation can only be used once.)", p_annotation);
		return false;
	}
#endif 
	this->_is_tool = true;
	return true;
}
bool GDScriptParser::icon_annotation(const AnnotationNode *p_annotation, Node *p_node) {
	ERR_FAIL_COND_V_MSG(p_node->type != Node::CLASS, false, R"("@icon" annotation can only be applied to classes.)");
	ERR_FAIL_COND_V(p_annotation->resolved_arguments.is_empty(), false);
	ClassNode *p_class = static_cast<ClassNode *>(p_node);
#ifdef DEBUG_ENABLED
	if (!p_class->icon_path.is_empty()) {
		push_error(R"("@icon" annotation can only be used once.)", p_annotation);
		return false;
	}
	if (String(p_annotation->resolved_arguments[0]).is_empty()) {
		push_error(R"("@icon" annotation argument must contain the path to the icon.)", p_annotation->arguments[0]);
		return false;
	}
#endif 
	p_class->icon_path = p_annotation->resolved_arguments[0];
	return true;
}
bool GDScriptParser::onready_annotation(const AnnotationNode *p_annotation, Node *p_node) {