The path was hardcoded in response cookie when enable the ingress controller dynamic-configuration

[hchenxa]

I was trying to use the session affinity when enable the dynamic-configuration, found the path will always be / in this case, I check the sticky.lua and found the path was hardcoded now.
refer https://github.com/kubernetes/ingress-nginx/blob/master/rootfs/etc/nginx/lua/balancer/sticky.lua#L44

NGINX Ingress controller version:
0.19.0

Kubernetes version (use kubectl version):
v 1.11.1