### 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
Member(ClassNode *p_class) {
				type = CLASS;
				m_class = p_class;
			}
			Member(ConstantNode *p_constant) {
				type = CONSTANT;
				constant = p_constant;
			}
			Member(VariableNode *p_variable) {
				type = VARIABLE;
				variable = p_variable;
			}
			Member(SignalNode *p_signal) {
				type = SIGNAL;
				signal = p_signal;
			}
			Member(FunctionNode *p_function) {
				type = FUNCTION;
				function = p_function;
			}
			Member(EnumNode *p_enum) {
				type = ENUM;
				m_enum = p_enum;
			}
			Member(const EnumNode::Value &p_enum_value) {
				type = ENUM_VALUE;
				enum_value = p_enum_value;
			}
			Member(AnnotationNode *p_annotation) {