### 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
r_error = ERR_COMPILATION_FAILED;
							return GDScriptCodeGenerator::Address();
						}
					} else {
						r_error = ERR_COMPILATION_FAILED;
						return GDScriptCodeGenerator::Address();
					}
				}
			}
			for (int i = 0; i < arguments.size(); i++) {
				if (arguments[i].mode == GDScriptCodeGenerator::Address::TEMPORARY) {
					gen->pop_temporary();
				}
			}
			return result;
		} break;
		case GDScriptParser::Node::GET_NODE: {
			const GDScriptParser::GetNodeNode *get_node = static_cast<const GDScriptParser::GetNodeNode *>(p_expression);
			Vector<GDScriptCodeGenerator::Address> args;
			args.push_back(codegen.add_constant(NodePath(get_node->full_path)));
			GDScriptCodeGenerator::Address result = codegen.add_temporary(_gdtype_from_datatype(get_node->get_datatype(), codegen.script));
			MethodBind *get_node_method = ClassDB::get_method("Node", "get_node");
			gen->write_call_ptrcall(result, GDScriptCodeGenerator::Address(GDScriptCodeGenerator::Address::SELF), get_node_method, args);
			return result;
		} break;
		case GDScriptParser::Node::PRELOAD: {
			const GDScriptParser::PreloadNode *preload = static_cast<const GDScriptParser::PreloadNode *>(p_expression);
			
			return codegen.add_constant(preload->resource);
		} break;