fix(persistent_sessions): Enhance documentation

apps/emqx/i18n/emqx_schema_i18n.conf

@@ -511,8 +511,8 @@ emqx_schema {
 
   persistent_session_store_backend {
     desc {
-        en: "Database backend used to store information about the persistent sessions.\n"
+        en: "Database management system used to store information about persistent sessions and messages.\n"
-            "- `builtin`: Use an embedded database (mria)"
+            "- `builtin`: Use the embedded database (mria)"
         zh: "用于存储持久性会话信息的数据库后端\n"
             "- `builtin`: 使用内置的数据库（mria）"
     }
@@ -524,7 +524,9 @@ emqx_schema {
 
   persistent_store_on_disc {
     desc {
-        en: "Persist session data on disc. If `false`, the data will be stored in RAM."
+        en: "Save information about the persistent sessions on disc.\n"
+            "If this option is enabled, persistent sessions will survive full restart of the cluster.\n"
+            "Otherwise, all the data will be stored in RAM, and it will be lost when all the nodes in the cluster are stopped."
         zh: "将会话数据保存在磁盘上。如果为 `false` 则存储在内存中。"
     }
     label: {
@@ -587,7 +589,7 @@ emqx_schema {
 
   persistent_session_builtin_session_table {
     desc {
-         en: "Tuning for built-in session table."
+         en: "Performance tuning options for built-in session table."
          zh: "对内置的会话表进行调整。"
     }
     label: {
@@ -598,7 +600,7 @@ emqx_schema {
 
   persistent_session_builtin_sess_msg_table {
     desc {
-         en: "Tuning for built-in session messages table."
+         en: "Performance tuning options for built-in session messages table."
          zh: "对内置的会话信息表进行调整。"
     }
     label: {
@@ -609,7 +611,7 @@ emqx_schema {
 
   persistent_session_builtin_messages_table {
     desc {
-         en: "Tuning for built-in messages table."
+         en: "Performance tuning options for built-in messages table."
          zh: "优化内置消息表配置。"
     }
     label: {