v5 first request is ~10x slower than v4

[grosser]

Problem: the first request of a new client is somehow 10x slower on v5 (100ms vs 10ms)

Background: I was trying to upgrade our app to v5 (master) to get gzip to resolve #622

c = build_kubeclient(@url, 'api/v1')
Benchmark.realtime { c.get_entity("namespaces", "kube-system") }
master: 0.017
v5: 0.10

since I'm using get_entity I don't think the issue is extra requests, but something is going on ...