Add missing nuget8.config

Author: radical

src/mono/wasm/Wasm.Build.Tests/data/nuget8.config

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<configuration>
+  <!-- Don't use any higher level config files. -->
+  <fallbackPackageFolders>
+    <clear />
+    <!--<add key="local" value="##\c " />-->
+  </fallbackPackageFolders>
+  <packageSources>
+    <clear />
+    <!-- TEST_RESTORE_SOURCES_INSERTION_LINE -->
+    <add key="dotnet8" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/dotnet8/nuget/v3/index.json" />
+    <add key="nuget.org"  value="https://api.nuget.org/v3/index.json" protocolVersion="3" />
+  </packageSources>
+    <disabledPackageSources>
+    <clear />
+  </disabledPackageSources>
+</configuration>