.NET Core support status

[alexalok]

.NET Core 3.x

• ApnsClient.ConnectUsingJwt()
• ApnsClient.ConnectUsingCert()

.NET Core 2.x

• ApnsClient.ConnectUsingJwt() - works if AppContext.SetSwitch("System.Net.Http.UseSocketsHttpHandler", false); is specified somewhere in the program before the connection is created.
• ApnsClient.ConnectUsingCert() - doesn't work and probably will never do. Gets the same exception as in .NET Framework (see Expose the constructor so that a custom HttpClient can be passed in. #3, .NET Framework support #4)