Remove redundant allocations

[Pliner]

Proposed Changes

This PR removes several unneccessary allocations:

1. Enumerator of List.
2. Encoding inside BinaryReader and BinaryWriter.

Types of Changes

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• Bugfix (non-breaking change which fixes issue #NNNN)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation (correction or otherwise)
• Cosmetics (whitespace, appearance)

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Further Comments

Producer.cs

    public static class EntryPoint
    {
        public static void Main(string[] args)
        {
            var connectionFactory = new ConnectionFactory();
            using (var connection = connectionFactory.CreateConnection())
            {
                using (var model = connection.CreateModel())
                {
                    model.ExchangeDeclare("Exchange", "direct", true);
                    for (var i = 0; i < 10000; ++i)
                    {
                        model.BasicPublish("Exchange", "#", body: new byte[100000]);
                    }
                }
            }   

            Console.ReadKey();
        }
    }

Before.zip

After.zip

As you can see, after this change amount of allocated objects dropped by 1/4. Also it seems the next major improvement can be a replace of NetworkBinaryReader and NetworkBinaryWriter, which will not allocate so much trash 😜

[kjnilsson]

Thanks!

[kjnilsson]

This change should be in https://www.nuget.org/packages/RabbitMQ.Client/6.0.0-pre3