public async Task PayloadHashContentTest()
{
var signer = new AwsSigner();
var content = new StringContent("Hello World!", Encoding.UTF8, "text/plain");
const string expected = "7f83b1657ff1fc53b92dc18148a1d65dfc2d4b1fa3d677284addd200126d9069";
var output = await signer.HashPayload(content);
Assert.AreEqual(expected, output, "Payload hash failed");
}