Polyglot Notebook: [DevExE2E] When saving the newly created .dib/ipynb file, the cell execution results will be disappeared and these files still in unsaved status.

[v-hozha1]

Describe the bug
When saving the newly created .dib/ipynb file, the cell execution results will be disappeared and these files still in unsaved status. If we want to close them, it will reminder us "Do you want to save the changes you made to..."

Detailed Repro Build info:
VSCodeSetup-x64-1.90.0 + dotnet-interactive-vscode-1.0.5312031.vsix + dotnet-sdk-8.0.302-win-x64

VS Code link: https://code.visualstudio.com/download#
Version: 1.90.0 (system setup)
Commit: 89de5a8d4d6205e5b11647eb6a74844ca23d2573
Date: 2024-06-04T19:33:54.889Z
Electron: 29.4.0
ElectronBuildId: 9593362
Chromium: 122.0.6261.156
Node.js: 20.9.0
V8: 12.2.281.27-electron.0
OS: Windows_NT x64 10.0.19045

dotnet-interactive-vscode-1.0.5312031.vsix
https://dev.azure.com/dnceng/internal/_build/results?buildId=2472419&view=artifacts&pathAsName=false&type=publishedArtifacts

Steps:
1.Ctrl+Shift+P` => "Polyglot Notebook: Create new blank notebook"
2.Select "Create as .ipynb"
3.Select "F#"
4.Set the cell contents to 1+1 and execute.
5.Save the file to disk
6. Check the files status in VSCode page.

Expected Results:
The files should be saved in disk normally and the execution results should still shown in VSCode page.

Actual Results:
When saving the newly created .dib/ipynb file, the cell execution results will be disappeared and these files still in unsaved status. If we want to close them, it will reminder us "Do you want to save the changes you made to..."

Please complete the following:

Which version of .NET Interactive are you using? (In a notebook, run the #!about magic command. ):

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[pkese]

I think that the .dib files are not supposed to store cell outputs anyway.
See: https://accessibleai.dev/post/polyglot_dib_vs_ipynb/

.ipynb files however should store outputs, but apparently there's a bug that the contents of the files disappear after opening. See #3335