`system_distributed_everywhere` is a new keyspace that uses Everywhere
replication strategy. This is useful, for example, when we want to store
internal data that should be accessible by every node; the data can be
written using CL=ALL (e.g. during node operations such as node
bootstrap, which require all nodes to be alive - at least currently) and
then read by each node locally using CL=ONE (e.g. during node restarts).
Closes#8457
617813ba66