### 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 (r_error) {
			memdelete(codegen.generator);
			return nullptr;
		}
	}
#ifdef DEBUG_ENABLED
	if (EngineDebugger::is_active()) {
		String signature;
		
		if (!p_script->get_script_path().is_empty()) {
			signature += p_script->get_script_path();
		}
		
		if (p_func) {
			signature += "::" + itos(p_func->body->start_line);
		} else {
			signature += "::0";
		}
		
		if (p_class->identifier) {
			signature += "::" + String(p_class->identifier->name) + "." + String(func_name);
		} else {
			signature += "::" + String(func_name);
		}
		if (p_for_lambda) {
			signature += "(lambda)";
		}
		codegen.generator->set_signature(signature);
	}
#endif