Consider changing cluster membership to not rely on clock time

[purplefox]

The current cluster membership eviction algorithm requires on clocks to be synced between members so that members are evicted after the proper time without updating themselves. If clocks are not synced - this could result in members being evicted too quickly or not evicted when they should be after failing.

We can consider a different membership algorithm where, instead of maintaining last updated time on each member in the shared state, we maintain a number of pings count which is incremented every time a member updates themself. If a member hasn't updated themself enough times since the last check, they are evicted.