### 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
if (is_finite) {
							number_str = number_str.pad_decimals(min_decimals);
						}
						int initial_len = number_str.length();
						// 
						int pad_chars_count = val < 0 ? min_chars - 1 : min_chars;
						 pad_char = (pad_with_zeros && is_finite) ? ("0") : (" "); // 
						if (left_justified) {
							number_str = number_str.rpad(pad_chars_count, pad_char);
						} else {
							number_str = number_str.lpad(pad_chars_count, pad_char);
						}
						// 
						if (val < 0) {
							if (left_justified) {
								number_str = number_str.insert(0, "-");
							} else {
								number_str = number_str.insert(pad_with_zeros ? 0 : number_str.length() - initial_len, "-");
							}
						}
						// 
						str += number_str;
						if (i < count - 1) {
							str += ", ";
						}
					}
					str += ")";
					formatted += str;
					++value_index;
					in_format = false;