test: add WaitGroup delta before goroutine
test: add WaitGroup delta before goroutine

To avoid a WaitGroup.Wait() being executed without the
execution of Add(1), the Add(1) should be perform before a go routine
initialization.

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

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