update dotnet version

Author: afifi-ins

NuGet.config

@@ -5,8 +5,6 @@
     <add key="dotnet-eng" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet-eng/nuget/v3/index.json" />
     <add key="dotnet-tools" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet-tools/nuget/v3/index.json" />
     <add key="dotnet-public" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet-public/nuget/v3/index.json" />
-    <add key="nuget" value="https://api.nuget.org/v3/index.json" />
-    <add key="CoreWCF_Dev" value="https://pkgs.dev.azure.com/dotnet/CoreWCF/_packaging/CoreWCF/nuget/v3/index.json" />
   </packageSources>
   <disabledPackageSources />
 </configuration>

eng/SendToHelix.proj

@@ -19,7 +19,7 @@
 
   <Target Name="InstallDotNet">
     <ItemGroup>
-      <AdditionalDotNetPackage Include="8.0.5">
+      <AdditionalDotNetPackage Include="8.0.8">
         <PackageType>aspnetcore-runtime</PackageType>
         <Channel>Current</Channel>
       </AdditionalDotNetPackage>