### 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_multiline(true);
		advance();
		do {
			if (check(GDScriptTokenizer::Token::PARENTHESIS_CLOSE)) {
				
				break;
			}
			ParameterNode *parameter = parse_parameter();
			if (parameter == nullptr) {
				push_error("Expected signal parameter name.");
				break;
			}
			if (parameter->initializer != nullptr) {
				push_error(R"(Signal parameters cannot have a default value.)");
			}
			if (signal->parameters_indices.has(parameter->identifier->name)) {
				push_error(vformat(R"(Parameter with name "%s" was already declared for this signal.)", parameter->identifier->name));
			} else {
				signal->parameters_indices[parameter->identifier->name] = signal->parameters.size();
				signal->parameters.push_back(parameter);
			}
		} while (match(GDScriptTokenizer::Token::COMMA) && !is_at_end());
		pop_multiline();
		consume(GDScriptTokenizer::Token::PARENTHESIS_CLOSE, R"*(Expected closing ")" after signal parameters.)*");
	}
	complete_extents(signal);
	end_statement("signal declaration");
	return signal;
}
GDScriptParser::EnumNode *GDScriptParser::parse_enum(bool p_is_static) {