BunnyCDNStorage:: async Task DownloadObjectAsync use FileStream.CopyToAsync and await

[benrussill]

REASON: cleaner code and CopyToAsync performance

• https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/using-statement`

• https://docs.microsoft.com/en-us/dotnet/api/system.io.filestream.copytoasync?view=net-6.0

using (var bufferedStream = new BufferedStream(stream, 1024 * 64))
{
using (var fileStream = new FileStream(localFilePath, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.ReadWrite, 1024 * 64))
{
bufferedStream.CopyTo(fileStream, 1024 * 64);
}
}

CHANGE TO

using var bufferedStream = new BufferedStream(stream, 1024 * 64);

using var fileStream = new FileStream(localFilePath, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.ReadWrite, 1024 * 64);

await bufferedStream.CopyToAsync(fileStream, 1024 * 64);