fix broken links

Author: PhilKang0704

articles/ai-services/speech-service/includes/release-notes/release-notes-sdk.md

@@ -853,7 +853,6 @@ This table shows the previous and new object names for real-time diarization and
 - **ObjectiveC**: Added sample for keyword recognition [here](https://github.com/Azure-Samples/cognitive-services-speech-sdk/tree/master/samples/objective-c/ios/speech-samples).
 - **C#/JavaScript**: Added quickstart for conversation transcription [here (C#)](https://github.com/Azure-Samples/cognitive-services-speech-sdk/tree/master/quickstart/csharp/dotnet/conversation-transcription) and [here (JavaScript)](https://github.com/Azure-Samples/cognitive-services-speech-sdk/tree/master/quickstart/javascript/node/conversation-transcription).
 - **C++/C#/Java/Python/Swift/ObjectiveC**: Added sample for Pronunciation Assessment [here](https://github.com/Azure-Samples/cognitive-services-speech-sdk/tree/master/samples)
-- **Xamarin**: Updated quickstart to latest Visual Studio template [here](https://github.com/Azure-Samples/cognitive-services-speech-sdk/tree/master/quickstart/csharp/xamarin).
 
 #### Known Issue
 - DigiCert Global Root G2 certificate isn't supported by default in HoloLens 2 and Android 4.4 (KitKat) and needs to be added to the system to make the Speech SDK functional. The certificate will be added to HoloLens 2 OS images in the near future. Android 4.4 customers need to add the updated the certificate to the system.