docs: hide core_nodes config doc

core_nodes config is no longer required.

apps/emqx_conf/src/emqx_conf_schema.erl

@@ -154,6 +154,8 @@ fields("cluster") ->
             sc(
                 node_array(),
                 #{
+                    %% This config is nerver needed (since 5.0.0)
+                    importance => ?IMPORTANCE_HIDDEN,
                     mapping => "mria.core_nodes",
                     default => [],
                     'readOnly' => true,

rel/i18n/emqx_conf_schema.hocon

@@ -389,17 +389,6 @@ cluster_mcast_ttl.desc:
 cluster_mcast_ttl.label:
 """Cluster Multicast TTL"""
 
-db_core_nodes.desc:
-"""List of core nodes that the replicant will connect to.<br/>
-Note: this parameter only takes effect when the <code>backend</code> is set
-to <code>rlog</code> and the <code>role</code> is set to <code>replicant</code>.<br/>
-This value needs to be defined for manual or static cluster discovery mechanisms.<br/>
-If an automatic cluster discovery mechanism is being used (such as <code>etcd</code>),
-there is no need to set this value."""
-
-db_core_nodes.label:
-"""Db Core Node"""
-
 log_file_handler_file.desc:
 """Name the log file."""