feat(backend): support replication of postgresql

Resolve #10205

chart/files/default.yml

@@ -72,6 +72,23 @@ db:
   #extra:
   #  ssl: true
 
+dbReplications: false
+
+# You can configure any number of replicas here
+#dbSlaves:
+#  -
+#    host: 
+#    port: 
+#    db: 
+#    user: 
+#    pass: 
+#  -
+#    host: 
+#    port: 
+#    db: 
+#    user: 
+#    pass: 
+
 #   ┌─────────────────────┐
 #───┘ Redis configuration └─────────────────────────────────────