Dockerfile: Use proxy with legacy fix
Dockerfile: Use proxy with legacy fix

Use cilium-envoy with a fix for regression that broke support for
Cilium versions without TPROXY support (< 1.6).

Signed-off-by: Jarno Rajahalme <0f1ab0ac7dffd9db21aa539af2fd4bb04abc3ad4@covalent.io>

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