tests: ease debugging TestClientEndpoint_CreateNodeEvals
tests: ease debugging TestClientEndpoint_CreateNodeEvals

TestClientEndpoint_CreateNodeEvals flakes a bit but its output is very
confusing, as `structs.Evaluations` overrides GoString.

Here, we emit the entire struct of the evaluation, and hopefully we'll
figure out the problem the next time it happens

burdandrei/nomad,dvusboy/nomad,hashicorp/nomad,burdandrei/nomad,dvusboy/nomad,hashicorp/nomad,burdandrei/nomad,burdandrei/nomad,dvusboy/nomad,burdandrei/nomad,burdandrei/nomad,dvusboy/nomad,dvusboy/nomad,hashicorp/nomad,burdandrei/nomad,hashicorp/nomad,dvusboy/nomad,dvusboy/nomad,hashicorp/nomad,hashicorp/nomad