Update nuget.config

nuget.config

@@ -4,7 +4,5 @@
   <packageSources>
     <clear />
     <add key="api.nuget.org" value="https://api.nuget.org/v3/index.json" />
-    <add key="avalonia" value="https://nuget.avaloniaui.net/repository/avalonia-all/index.json" protocolVersion="3" />
-    <add key="skiasharp" value="https://aka.ms/skiasharp-eap/index.json" protocolVersion="3" />
   </packageSources>
 </configuration>