Fix TcpListener disposal in ReadLineAsync_AfterDispose_ReturnsNull test#270

HowardvanRooijen merged 2 commits intofeature/dotnet-10-updateais-dotnet/Ais.Net.Receiver:feature/dotnet-10-updatefrom

copilot/sub-pr-267-another-oneais-dotnet/Ais.Net.Receiver:copilot/sub-pr-267-another-oneCopy head branch name to clipboard