### 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
#endif
	buf[324] = 0;
	
	{
		bool period = false;
		int z = 0;
		while (buf[z]) {
			if (buf[z] == '.') {
				period = true;
			}
			z++;
		}
		if (period) {
			z--;
			while (z > 0) {
				if (buf[z] == '0') {
					buf[z] = 0;
				} else if (buf[z] == '.') {
					buf[z] = 0;
					break;
				} else {
					break;
				}
				z--;
			}
		}
	}
	return buf;
}
 ::num_int64(int64_t p_num, int base, bool capitalize_hex) {