Add comment about SourceBuildPrebuilt versions (#47935)

* Add comment about SourceBuildPrebuilt versions

* Update

Author: wtgodbe

eng/Versions.props

@@ -141,6 +141,7 @@
     <MicrosoftCodeAnalysisCSharpVersion>4.4.0-4.22520.2</MicrosoftCodeAnalysisCSharpVersion>
     <MicrosoftCodeAnalysisCSharpWorkspacesVersion>4.4.0-4.22520.2</MicrosoftCodeAnalysisCSharpWorkspacesVersion>
     <!-- Packages from NuGet/Nuget.client -->
+    <!-- If you update these versions, make sure to also update https://github.com/dotnet/aspnetcore/blob/main/eng/SourceBuildPrebuiltBaseline.xml -->
     <NuGetPackagingVersion>6.2.2</NuGetPackagingVersion>
     <NuGetVersioningVersion>6.2.2</NuGetVersioningVersion>
     <NuGetFrameworksVersion>6.2.2</NuGetFrameworksVersion>
@@ -224,9 +225,11 @@
     <!--
       Versions of Microsoft.CodeAnalysis packages referenced by analyzers shipped in the SDK.
       This need to be pinned since they're used in 3.1 apps and need to be loadable in VS 2019.
+      If you update these versions, make sure to also update https://github.com/dotnet/aspnetcore/blob/main/eng/SourceBuildPrebuiltBaseline.xml
     -->
     <Analyzer_MicrosoftCodeAnalysisCSharpVersion>3.3.1</Analyzer_MicrosoftCodeAnalysisCSharpVersion>
     <Analyzer_MicrosoftCodeAnalysisCSharpWorkspacesVersion>3.3.1</Analyzer_MicrosoftCodeAnalysisCSharpWorkspacesVersion>
+
     <MicrosoftCodeAnalysisExternalAccessAspNetCoreVersion>4.4.0-4.22520.2</MicrosoftCodeAnalysisExternalAccessAspNetCoreVersion>
     <MicrosoftCodeAnalysisCommonVersion>4.4.0-4.22520.2</MicrosoftCodeAnalysisCommonVersion>
     <MicrosoftCodeAnalysisCSharpVersion>4.4.0-4.22520.2</MicrosoftCodeAnalysisCSharpVersion>