Updated versioning information in `DigitalData.Core.Abstractions.csproj` from 3.6.0 to 4.0.0, including changes to `<Version>`, `<AssemblyVersion>`, and `<FileVersion>`.
Updated versioning information in `DigitalData.Core.Abstractions.csproj` from 3.6.0 to 4.0.0, including changes to `<Version>`, `<AssemblyVersion>`, and `<FileVersion>`.