Unlike other experimental feature we want to raft to be opt in even
after it leaves experimental mode. For that we need to have a separate
option to enable it. The patch adds the binary option "consistent-cluster-management"
for that.
* 'consistent-cluster-management-flag' of github.com:scylladb/scylla-dev:
raft: replace experimental raft option with dedicated flag
main: move supervisor notification about group registry start where it actually starts
09da661eeb