Support *.dib format for manage notebook file that only code snippet exclusive.

[Creta5164]

I found out that the ipynb format includes the contents of the execution results in the file.

However, I felt that it creates too many changes to the file, and makes it difficult to manage the version or resolve conflicts in the notebook file itself in the repository.

So I would like to support the dib format of .NET interactive, which does not use it.