Correct Protobuf News announcement to remove clarification that individual DLL's will still be signed.

PiperOrigin-RevId: 936734497

Author: zhangskz

content/news/2026-06-16.md

@@ -15,8 +15,6 @@ Previously, we used a Google-owned certificate to author-sign NuGet packages.
 NuGet packages will no longer contain a Google author signature. They will
 continue to be repository-signed by nuget.org upon upload.
 
-Note that individual DLLs inside the package will remain signed. This change
-only affects the signature of the NuGet package container itself.
 
 This change aligns with similar signing changes being made to the gRPC NuGet
 packages.