Add --code-only feature to pulumi import, getting code without updating stack/state

[glitchwizard]

Currently we can use pulumi import, and doing so updates the state of the stack imported. It would be great to have the something like pulumi import --code-only where it only gets the code and does not update the state of the stack.

Currently the only way we know how to do this is run pulumi import and then delete the most recent updated stack state.

Affected feature

pulumi import would be affected, giving it an option to exclude updating the state of the stack upon import. This would allow us to get the code for the part, somewhat like a template, and then use it elsewhere, without having to worry about the state of our stack potentially changing.

[mikhailshilkov]

This is very close to #8836 so we'll use that issue to track this improvement