feat(signing): use new signing

[bcuff]

Use new signing technique that allows for all http headers to be accounted for correctly. This may fix signing when http compression is turned on.

[zhuvaka]

This new signing technique seems to be working fine. I tested it with AWS elastic cluster of version 7.9 Iit works fine for both open and private security settings. Here is snippet of code I have

var httpConnection = new AwsHttpConnection();
            var connectionPool = new SingleNodeConnectionPool(new Uri(nodeUrl));
            var settings = new ConnectionSettings(connectionPool, httpConnection)
                .DefaultIndex(indexName)
                .EnableHttpCompression()
                .ThrowExceptions();

            var client = new ElasticClient<T>(settings);

Looking forward to see updated nuget package @bcuff

[bcuff]

@zhuvaka published in 7.2.0