testutils: Add WaitUntilWithSleep
testutils: Add WaitUntilWithSleep

As for some cases WaitUntil() is a DoS tool.

Signed-off-by: Martynas Pumputis <6b0d31c0d563223024da45691584643ac78c96e8@lambda.lt>

tklauser/cilium,michi-covalent/cilium,michi-covalent/cilium,tklauser/cilium,cilium/cilium,michi-covalent/cilium,cilium/cilium,michi-covalent/cilium,michi-covalent/cilium,tklauser/cilium,tklauser/cilium,cilium/cilium,cilium/cilium,cilium/cilium,tklauser/cilium