Update NuGet.Config (#6873) (#6933)

Co-authored-by: Reuben Bond <[email protected]>

Author: benjaminpetit

NuGet.Config

@@ -1,9 +1,10 @@
 <?xml version="1.0" encoding="utf-8"?>
 <configuration>
   <packageSources>
+    <clear />
     <add key="nuget.org" value="https://api.nuget.org/v3/index.json" protocolVersion="3" />
   </packageSources>
   <solution>
     <add key="disableSourceControlIntegration" value="true" />
   </solution>
-</configuration>
+</configuration>