### 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
push_text("Assert ( ");
	print_expression(p_assert->condition);
	push_line(" )");
}
void GDScriptParser::TreePrinter::print_assignment(AssignmentNode *p_assignment) {
	switch (p_assignment->assignee->type) {
		case Node::IDENTIFIER:
			print_identifier(static_cast<IdentifierNode *>(p_assignment->assignee));
			break;
		case Node::SUBSCRIPT:
			print_subscript(static_cast<SubscriptNode *>(p_assignment->assignee));
			break;
		default:
			break; 
	}
	push_text(" ");
	switch (p_assignment->operation) {
		case AssignmentNode::OP_ADDITION:
			push_text("+");
			break;
		case AssignmentNode::OP_SUBTRACTION:
			push_text("-");
			break;
		case AssignmentNode::OP_MULTIPLICATION:
			push_text("*");
			break;
		case AssignmentNode::OP_DIVISION:
			push_text("/");