### 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
pop_multiline();
				complete_extents(call);
				return nullptr;
			}
			if (current_function->identifier) {
				call->function_name = current_function->identifier->name;
			} else {
				call->function_name = SNAME("<anonymous>");
			}
		} else {
			consume(GDScriptTokenizer::Token::PERIOD, R"(Expected "." or "(" after "super".)");
			make_completion_context(COMPLETION_SUPER_METHOD, call, true);
			if (!consume(GDScriptTokenizer::Token::IDENTIFIER, R"(Expected function name after ".".)")) {
				pop_multiline();
				complete_extents(call);
				return nullptr;
			}
			IdentifierNode *identifier = parse_identifier();
			call->callee = identifier;
			call->function_name = identifier->name;
			consume(GDScriptTokenizer::Token::PARENTHESIS_OPEN, R"(Expected "(" after function name.)");
		}
	} else {
		call->callee = p_previous_operand;
		if (call->callee == nullptr) {
			push_error(R"*(Cannot call on an expression. Use ".call()" if it's a Callable.)*");
		} else if (call->callee->type == Node::IDENTIFIER) {
			call->function_name = static_cast<IdentifierNode *>(call->callee)->name;
			make_completion_context(COMPLETION_METHOD, call->callee);
		} else if (call->callee->type == Node::SUBSCRIPT) {