Initialize HA cluster using an embedded etcd datastore.
If this option is false and role is server
On a server that was using the default embedded sqlite backend, enabling this option will migrate to an embedded etcd DB.
If an HA cluster using the embedded etcd datastore was already initialized, this option has no effect.
This option only makes sense in a server that is not connecting to another server.
If you are configuring an HA cluster with an embedded etcd, the 1st server must have clusterInit = true and other servers must connect to it using serverAddr.