### Godot version

4.1.1

### System information

linux

### Issue description

The `"%+f"` format adds a `+` sign in front of positive numbers. If you try to format `-0.0`, it breaks and displays both a `+` and a `-`.

### Steps to reproduce

```gdscript
@tool
extends EditorScript

func _run() -> void:
    print("%+f" % -0.0)
```

### Minimal reproduction project

see above
}
		} else { // 
			switch (c) {
				case '%':
					in_format = true;
					// 
					min_chars = 0;
					min_decimals = 6;
					pad_with_zeros = false;
					left_justified = false;
					show_sign = false;
					in_decimals = false;
					break;
				default:
					formatted += chr(c);
			}
		}
	}
	if (in_format) {
		return "incomplete format";
	}
	if (value_index != values.size()) {
		return "not all arguments converted during string formatting";
	}
	if (error) {
		*error = false;
	}
	return formatted;
}
 ::quote( quotechar) const {