Bump System.Collections.Immutable from 8.0.0 to 9.0.4#1923

mkaszewiak merged 1 commit intomaindotnet/Open-XML-SDK:mainfrom

dependabot/nuget/System.Collections.Immutable-9.0.4dotnet/Open-XML-SDK:dependabot/nuget/System.Collections.Immutable-9.0.4Copy head branch name to clipboard