operator: fix concurrent access of variable in cnp garbage collection
operator: fix concurrent access of variable in cnp garbage collection

As the cnp variable will be used in a different go routine we need to
deepcopy it.

Fixes: 0cd1be0e64dc ("operator: GC nodes from existing CNPs")
Signed-off-by: André Martins <bc9800b9d52a24cce72a73dd528afed53f10e5fc@cilium.io>

michi-covalent/cilium,cilium/cilium,tklauser/cilium,cilium/cilium,cilium/cilium,tklauser/cilium,tklauser/cilium,michi-covalent/cilium,tklauser/cilium,tgraf/cilium,tgraf/cilium,cilium-team/cilium,cilium/cilium,tklauser/cilium,michi-covalent/cilium,tgraf/cilium,cilium-team/cilium,tgraf/cilium,tgraf/cilium,michi-covalent/cilium,cilium/cilium,tgraf/cilium,michi-covalent/cilium