Update intro BETA status message.

Author: pglombardo

README.md

@@ -8,9 +8,9 @@
 [![Nuget](https://img.shields.io/nuget/dt/HiveMQtt?style=for-the-badge)](https://www.nuget.org/packages/HiveMQtt)
 [![GitHub](https://img.shields.io/github/license/hivemq/hivemq-mqtt-client-dotnet?style=for-the-badge)](https://github.com/hivemq/hivemq-mqtt-client-dotnet/blob/main/LICENSE)
 
-_This .NET MQTT client was put together with love from the HiveMQ team but is still in DEVELOPMENT.  As such some things may not work completely until it matures and although unlikely, APIs may change slightly before version 1.0._
+_This .NET MQTT client was put together with love from the HiveMQ team but is still in BETA.  While it's mostly stable, it is still under active development as we add new features.  If you have a feature request, [let us know](https://github.com/hivemq/hivemq-mqtt-client-dotnet/issues/new/choose)!._
 
-We'd appreciate any feedback you have.  Happy MQTT adventures!
+Happy MQTT adventures!
 
 * **Easy-to-Install**: Available as a [Nuget package](https://www.nuget.org/packages/HiveMQtt).
 * **Opensource**: No blackbox code.  Only trusted, tested and reviewed opensource code.