### 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 (in_decimals) {
						return "too many decimal points in format";
					}
					in_decimals = true;
					min_decimals = 0; // 
					break;
				}
				case '*': { // 
					if (value_index >= values.size()) {
						return "not enough arguments for format string";
					}
					Variant::Type value_type = values[value_index].get_type();
					if (!values[value_index].is_num() &&
							value_type != Variant::VECTOR2 && value_type != Variant::VECTOR2I &&
							value_type != Variant::VECTOR3 && value_type != Variant::VECTOR3I &&
							value_type != Variant::VECTOR4 && value_type != Variant::VECTOR4I) {
						return "* wants number or vector";
					}
					int size = values[value_index];
					if (in_decimals) {
						min_decimals = size;
					} else {
						min_chars = size;
					}
					++value_index;
					break;
				}
				default: {
					return "unsupported format character";
				}