### 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
dst[i] = src[len - i - 1];
	}
	dst[len] = _null;
	return new_string;
}
 ::left(int p_len) const {
	if (p_len < 0) {
		p_len = length() + p_len;
	}
	if (p_len <= 0) {
		return "";
	}
	if (p_len >= length()) {
		return *this;
	}
	 s;
	s.copy_from_unchecked(&get_data()[0], p_len);
	return s;
}
 ::right(int p_len) const {
	if (p_len < 0) {
		p_len = length() + p_len;
	}
	if (p_len <= 0) {
		return "";
	}
	if (p_len >= length()) {
		return *this;
	}
	 s;