### 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
REQUIRE(error == false);
	CHECK(output == String("fish A frog"));
	
	format = "fish %c frog";
	args.clear();
	args.push_back(65);
	output = format.sprintf(args, &error);
	REQUIRE(error == false);
	CHECK(output == String("fish A frog"));
	
	
	format = "fish %*s frog";
	args.clear();
	args.push_back(10);
	args.push_back("cheese");
	output = format.sprintf(args, &error);
	REQUIRE(error == false);
	REQUIRE(output == String("fish     cheese frog"));
	
	format = "fish %*d frog";
	args.clear();
	args.push_back(10);
	args.push_back(99);
	output = format.sprintf(args, &error);
	REQUIRE(error == false);
	REQUIRE(output == String("fish         99 frog"));
	
	format = "fish %*.*f frog";
	args.clear();
	args.push_back(10);