Fixing API contract

Author: stebet

projects/RabbitMQ.Client/PublicAPI.Unshipped.txt

@@ -848,7 +848,7 @@ static RabbitMQ.Client.Events.CallbackExceptionEventArgs.Build(System.Exception
 static RabbitMQ.Client.ExchangeType.All() -> System.Collections.Generic.ICollection<string>
 static RabbitMQ.Client.IChannelExtensions.BasicPublishAsync(this RabbitMQ.Client.IChannel channel, RabbitMQ.Client.CachedString exchange, RabbitMQ.Client.CachedString routingKey, System.ReadOnlyMemory<byte> body = default(System.ReadOnlyMemory<byte>), bool mandatory = false) -> System.Threading.Tasks.ValueTask
 static RabbitMQ.Client.IChannelExtensions.BasicPublishAsync(this RabbitMQ.Client.IChannel channel, string exchange, string routingKey, System.ReadOnlyMemory<byte> body = default(System.ReadOnlyMemory<byte>), bool mandatory = false) -> System.Threading.Tasks.ValueTask
-static RabbitMQ.Client.IChannelExtensions.BasicPublishAsync<T>(this RabbitMQ.Client.IChannel! channel, RabbitMQ.Client.PublicationAddress! addr, in T basicProperties, System.ReadOnlyMemory<byte> body) -> System.Threading.Tasks.ValueTask
+static RabbitMQ.Client.IChannelExtensions.BasicPublishAsync<T>(this RabbitMQ.Client.IChannel channel, RabbitMQ.Client.PublicationAddress addr, in T basicProperties, System.ReadOnlyMemory<byte> body) -> System.Threading.Tasks.ValueTask
 static RabbitMQ.Client.PublicationAddress.Parse(string uriLikeString) -> RabbitMQ.Client.PublicationAddress
 static RabbitMQ.Client.PublicationAddress.TryParse(string uriLikeString, out RabbitMQ.Client.PublicationAddress result) -> bool
 static RabbitMQ.Client.QueueDeclareOk.implicit operator string(RabbitMQ.Client.QueueDeclareOk declareOk) -> string