### 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
advance();
			result = parse_match();
			break;
		case GDScriptTokenizer::Token::BREAK:
			advance();
			result = parse_break();
			break;
		case GDScriptTokenizer::Token::CONTINUE:
			advance();
			result = parse_continue();
			break;
		case GDScriptTokenizer::Token::RETURN: {
			advance();
			ReturnNode *n_return = alloc_node<ReturnNode>();
			if (!is_statement_end()) {
				if (current_function && (current_function->identifier->name == GDScriptLanguage::get_singleton()->strings._init || current_function->identifier->name == GDScriptLanguage::get_singleton()->strings._static_init)) {
					push_error(R"(Constructor cannot return a value.)");
				}
				n_return->return_value = parse_expression(false);
			} else if (in_lambda && !is_statement_end_token()) {
				
				
				n_return->return_value = parse_expression(false);
			}
			complete_extents(n_return);
			result = n_return;
			current_suite->has_return = true;
			end_statement("return statement");
			break;
		}