### 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
s = *this;
	int c = s.find(".");
	if (c == -1) {
		if (p_digits <= 0) {
			return s;
		}
		s += ".";
		c = s.length() - 1;
	} else {
		if (p_digits <= 0) {
			return s.substr(0, c);
		}
	}
	if (s.length() - (c + 1) > p_digits) {
		return s.substr(0, c + p_digits + 1);
	} else {
		int zeros_to_add = p_digits - s.length() + (c + 1);
		return s + ("0").repeat(zeros_to_add);
	}
}
 ::pad_zeros(int p_digits) const {