[#583][Delta] Ensure resources are properly sent again if envoy unsubscribes then subscribes again to a resource#586

Draft

valerian-roche wants to merge 3 commits intoenvoyproxy:mainfrom valerian-roche:vr/delta-subscribe

+295-242

Commits on Aug 25, 2022

Rework Cache interface to isolate it from streamState and make it more uniform between sotw and delta
valerian-roche
committed
Fix unittest update wrongly inverted an assert
valerian-roche
committed
[envoyproxy#583 ][Delta] Ensure resources are properly sent again if envoy unsubscribes then subscribes again to a resource
valerian-roche
committed