Deprecation warning

[navidcy]

Could we add a deprecation warning that will appear once users call import cosima_cookbook that would inform them that ACCESS-NRI Intake catalog is preferred?

Is this a good idea?

cc @AndyHoggANU, @aekiss, @anton-seaice, @angus-g

[anton-seaice]

Its good in theory ... but I don't think cms ever update the cosima-cookbook conda package anymore, so no user would ever see it.

[navidcy]

We'll ask them to do so.