### 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
if (found) {
				break;
			}
			cursor_line++;
			cursor_column = 1;
		}
		source = source.replace_first(String::chr(0xFFFF), String());
	}
	tokenizer.set_source_code(source);
	tokenizer.set_cursor_position(cursor_line, cursor_column);
	script_path = p_script_path;
	current = tokenizer.scan();
	
	
	while (current.type == GDScriptTokenizer::Token::ERROR || current.type == GDScriptTokenizer::Token::NEWLINE) {
		if (current.type == GDScriptTokenizer::Token::ERROR) {
			push_error(current.literal);
		}
		current = tokenizer.scan();
	}
#ifdef DEBUG_ENABLED
	
	if (current.type == GDScriptTokenizer::Token::TK_EOF) {
		
		Node *nd = alloc_node<PassNode>();
		nd->start_line = 1;
		nd->start_column = 0;
		nd->end_line = 1;
		nd->leftmost_column = 0;
		nd->rightmost_column = 0;