v6.5.0 release notes: add descriptions about tidb_store_batch_size (#20472) (#20484)

Author: ti-chi-bot

releases/release-6.5.0.md

@@ -319,6 +319,7 @@ Compared with TiDB [6.4.0-DMR](/releases/release-6.4.0.md), TiDB 6.5.0 introduce
 | [`tidb_server_memory_limit`](/system-variables.md#tidb_server_memory_limit-new-in-v640) | Modified | Changes the default value from `0` to `80%`. As the TiDB global memory control becomes GA, this default value change enables the memory control by default and sets the memory limit for a TiDB instance to 80% of the total memory by default. |
 | [`default_password_lifetime`](/system-variables.md#default_password_lifetime-new-in-v650) | Newly added | Sets the global policy for automatic password expiration to require users to change passwords periodically. The default value `0` indicates that passwords never expire. |
 | [`disconnect_on_expired_password`](/system-variables.md#disconnect_on_expired_password-new-in-v650) | Newly added | Indicates whether TiDB disconnects the client connection when the password is expired. This variable is read-only. |
+| [`tidb_store_batch_size`](/system-variables.md#tidb_store_batch_size) | Newly added | This variable is disabled by default, and the feature controlled by it is not stable yet. It is not recommended to modify this variable in production environments. |
 | [`password_history`](/system-variables.md#password_history-new-in-v650) | Newly added | This variable is used to establish a password reuse policy that allows TiDB to limit password reuse based on the number of password changes. The default value `0` means disabling the password reuse policy based on the number of password changes. |
 | [`password_reuse_interval`](/system-variables.md#password_reuse_interval-new-in-v650) | Newly added | This variable is used to establish a password reuse policy that allows TiDB to limit password reuse based on time elapsed. The default value `0` means disabling the password reuse policy based on time elapsed. |
 | [`tidb_auto_build_stats_concurrency`](/system-variables.md#tidb_auto_build_stats_concurrency-new-in-v650) | Newly added | This variable is used to set the concurrency of executing the automatic update of statistics. The default value is `1`.  |