Utf8ValueStringBuilder incorrectly uses bytesWritten as charsWritten causing misalignment

[Molth]

https://github.com/Cysharp/ZString/blob/master/src/ZString/Utf8ValueStringBuilder.cs#L414

        static void Main(string[] args)
        {
            var a = ((char)(0x7F + 1));
            var sb = new StringBuilder();
            sb.AppendFormat("{0,-10:D5} s", a);
            var sb2 = ZString.CreateUtf8StringBuilder();
            sb2.AppendFormat("{0,-10:D5} s", a);
            Console.WriteLine(sb.ToString() == sb2.ToString());
        }

[Molth]

https://github.com/Cysharp/Utf8StringInterpolation

var sb3 = Utf8String.Format($"{a,-10:D5} s");
Console.WriteLine(sb.ToString() == sb3.ToString());