WSL --unregister should not delete if system was imported in-place

[mvrius]

Is your feature request related to a problem? Please describe.
If a user uses --import-in-place, then the usage itself would be indicative of the user managing the lifetime of the root filesystem outside of WSL built-in management semantics; as such, WSL should not delete the root filesystem when doing "--unregister"

Describe the solution you'd like
One of two options:
A) Unregister should not delete user data when image was created with "import-in-place"
B) Unregister should never delete user data. There should be an --unregister and --delete command. Similar to this #9932 - but I think we should just have two options [--unregister] and [--delete]

Describe alternatives you've considered
The workaround is somewhat simple to just --terminate + copy the image somewhere else, then do unregister, but it's ugly.

[github-actions]

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Otherwise please attach logs by following the instructions below, your issue will not be reviewed unless they are added. These logs will help us understand what is going on in your machine.

How to collect WSL logs

Download and execute collect-wsl-logs.ps1 in an administrative powershell prompt:

Invoke-WebRequest -UseBasicParsing "https://raw.githubusercontent.com/microsoft/WSL/master/diagnostics/collect-wsl-logs.ps1" -OutFile collect-wsl-logs.ps1
Set-ExecutionPolicy Bypass -Scope Process -Force
.\collect-wsl-logs.ps1

The script will output the path of the log file once done.

If this is a networking issue, please use collect-networking-logs.ps1, following the instructions here

Once completed please upload the output files to this Github issue.

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[mvrius]

Logs are required for review from WSL team

If this a feature request, please reply with '/feature'. If this is a question, reply with '/question'. Otherwise please attach logs by following the instructions below, your issue will not be reviewed unless they are added. These logs will help us understand what is going on in your machine.

How to collect WSL logs

/feature

This was tagged already, this reply is really unnecessary.

[github-actions]

Diagnostic information

Found '/feature', adding tag 'feature'