pkg/node: add delete DeleteAllNodes() function
pkg/node: add delete DeleteAllNodes() function

This function has proven to be helpful in unit tests.

Signed-off-by: André Martins <bc9800b9d52a24cce72a73dd528afed53f10e5fc@cilium.io>

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