### 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
case GDScriptTokenizer::Token::BREAKPOINT:
			advance();
			result = alloc_node<BreakpointNode>();
			complete_extents(result);
			end_statement(R"("breakpoint")");
			break;
		case GDScriptTokenizer::Token::ASSERT:
			advance();
			result = parse_assert();
			break;
		case GDScriptTokenizer::Token::ANNOTATION: {
			advance();
			is_annotation = true;
			AnnotationNode *annotation = parse_annotation(AnnotationInfo::STATEMENT);
			if (annotation != nullptr) {
				annotation_stack.push_back(annotation);
			}
			break;
		}
		default: {
			
			ExpressionNode *expression = parse_expression(true); 
			bool has_ended_lambda = false;
			if (expression == nullptr) {
				if (in_lambda) {
					
					lambda_ended = true;
					has_ended_lambda = true;
				} else {
					advance();