C#: Update change note.

Author: michaelnebel

csharp/ql/lib/change-notes/2026-09-03-replaces-base.md

@@ -1,4 +1,4 @@
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 category: minorAnalysis
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-* Private NuGet registries for which the "Replaces base" option is enabled in the organization-level private registry configuration now replace `nuget.org` sources whenever dependencies are downloaded, including sources discovered from NuGet configuration.
+* Private NuGet registries for which the "Replaces base" option is enabled in the organization-level private registry configuration now replace default NuGet feeds whenever dependencies are downloaded, including when default NuGet feeds are configured explicitly for a project.