### 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
ERR_FAIL_COND_V_MSG(p_target->type != Node::CLASS, false, vformat(R"("%s" annotation can only be applied to classes.)", p_annotation->name));
	ClassNode *p_class = static_cast<ClassNode *>(p_target);
	if (p_class->annotated_static_unload) {
		push_error(vformat(R"("%s" annotation can only be used once per script.)", p_annotation->name), p_annotation);
		return false;
	}
	p_class->annotated_static_unload = true;
	return true;
}
GDScriptParser::DataType GDScriptParser::SuiteNode::Local::get_datatype() const {
	switch (type) {
		case CONSTANT:
			return constant->get_datatype();
		case VARIABLE:
			return variable->get_datatype();
		case PARAMETER:
			return parameter->get_datatype();
		case FOR_VARIABLE:
		case PATTERN_BIND:
			return bind->get_datatype();
		case UNDEFINED:
			return DataType();
	}
	return DataType();
}
String GDScriptParser::SuiteNode::Local::get_name() const {