Add a warning to avoid publisher from closing the cloud shell

[code4clouds]

Is your feature request related to a problem? Please describe.
As a publisher,
I would like a reminder to not close the cloudshell,
so I can copy the content of the SA... instead of automatically closing the window assuming is all done.

Describe the solution you'd like
A warning message.

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context
Add any other context or screenshots about the feature request here.