'ctl delete_shovel': adapt to rabbit_shovel_dyn_worker_sup_sup public API changes (backport #13244)

[mergify]

rabbit_shovel_dyn_worker_sup_sup doesn't export stop_and_delete_child

It exports stop_child which in turn calls stop_and_delete_child.

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This is an automatic backport of pull request #13244 done by [Mergify](https://mergify.com).