Update upgrade-cluster.md

During the upgrade process, you should only run the ./install.sh command.

The manual is unclear about this part and may be misleading.

Additional explanation is needed.
Ex) You may be confused about the install script when you first install redis and when you upgrade it.
# ./install.sh --install-dir /redis --var-dir /ifp_data/redis --config-dir /redis/config

2025-06-24 20:56:59.274 [x] Error: --install-dir cannot be set during upgrade.
..
2025-06-24 20:57:30.286 [x] Error: --var-dir cannot be set during upgrade.
..
2025-06-24 20:57:37.335 [x] Error: --config-dir cannot be set during upgrade.

Author: Virusuki

content/operate/rs/installing-upgrading/upgrading/upgrade-cluster.md

@@ -97,14 +97,19 @@ You cannot change the installation path or the user during the upgrade.
 
     The upgrade replaces all node processes, which might briefly interrupt any active connections.
 
-2.  Verify the node was upgraded to the new version and is still operational:
+    {{<note>}}
+You should only run the ./install.sh command while upgrade. 
+During the upgrade, --*-dir <dir> cannot be set, and an error will occur. Please note.
+    {{<note>}}
+    
+3.  Verify the node was upgraded to the new version and is still operational:
 
     ``` shell
     $ rlcheck
     $ rladmin status extra all
     ```
 
-3.  Visit the Cluster Manager UI.
+4.  Visit the Cluster Manager UI.
 
     If the Cluster Manager UI was open in a web browser during the upgrade, refresh the browser to reload the console.