[cq] remove straggling .packages support

[pq]

Fixes: #8722 and opportunistically removes some dead code.

Note: nothing urgent here; just tidying up! 🧹

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[parlough]

Love it. Thanks for this cleanup @pq!

[parlough]

Looks like I don't have write access to approve, so you'll need another reviewer, but looks good to me :)

[pq]

Love it. Thanks for this cleanup @pq!

Thanks for pointing out the opportunity!