SDK content diffs - .NET 9 Preview 1 - format

[ellahathaway]

Microsoft and source-built SDKs contain the following difference related to format content and packages. There should be no unintentional differences.

All intentional differences should be captured in SDK diff exclusion file:

Files only present in Microsoft-built SDK:

./sdk/x.y.z/DotnetTools/dotnet-format/Microsoft.CodeAnalysis.ExternalAccess.RazorCompiler.dll

Files only present in Source-built SDK:

./sdk/x.y.z/DotnetTools/dotnet-format/BuildHost-netcore/Microsoft.CodeAnalysis.Workspaces.MSBuild.BuildHost.deps.json
./sdk/x.y.z/DotnetTools/dotnet-format/System.Collections.Immutable.dll
./sdk/x.y.z/DotnetTools/dotnet-format/System.Reflection.Metadata.dll
./sdk/x.y.z/DotnetTools/dotnet-format/System.Text.Encodings.Web.dll
./sdk/x.y.z/DotnetTools/dotnet-format/System.Text.Json.dll

Related to #4013

[ghost]

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[ellahathaway]

./sdk/x.y.z/DotnetTools/dotnet-format/Microsoft.CodeAnalysis.ExternalAccess.RazorCompiler.dll is expected as discussed in #4016 (comment)