Add a note to Step 4 in Importing an interface into a command component section

[ifsheldon]

This adds a note to Step 4 in Importing an interface into a command component section, making the tutorial clearer.

I find this missing piece when I walked through the steps.

@kate-goldenring

[vados-cosmonic]

Hey @ifsheldon the Rust docs have been updated a bit -- I believe they should be right now! (the code that cargo component generates is now copy pasted). If you'd like to work through it again I'd appreciate it but I think your change should be incorporated now.

[ifsheldon]

OK, I saw the new changes. Thanks!