### 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
char32_t *dst = ptrw() + lhs_len;
	
	memcpy(dst, src, rhs_len * sizeof(char32_t));
	*(dst + rhs_len) = _null;
	return *this;
}
 &::operator+=(const char *p_str) {
	if (!p_str || p_str[0] == 0) {
		return *this;
	}
	const int lhs_len = length();
	const size_t rhs_len = strlen(p_str);
	resize(lhs_len + rhs_len + 1);
	char32_t *dst = ptrw() + lhs_len;
	for (size_t i = 0; i <= rhs_len; i++) {
		uint8_t c = p_str[i] >= 0 ? p_str[i] : uint8_t(256 + p_str[i]);
		if (c == 0 && i < rhs_len) {
			print_unicode_error("NUL character", true);
			dst[i] = _replacement_char;
		} else {
			dst[i] = c;
		}
	}
	return *this;
}
 &::operator+=(const wchar_t *p_str) {
#ifdef WINDOWS_ENABLED
	
	*this += ::utf16((const char16_t *)p_str);
#else