fix: update rpm link for version 2.6

Author: johzchen

docs/en/latest/deploy-with-rpm.md

@@ -26,7 +26,7 @@ title: Deploy with RPM
 ## Install from RPM
 
 ```sh
-$ sudo yum install -y https://github.com/apache/apisix-dashboard/releases/download/v2.4/apisix-dashboard-2.4-0.x86_64.rpm
+$ sudo yum install -y https://github.com/apache/apisix-dashboard/releases/download/v2.6/apisix-dashboard-2.6-0.x86_64.rpm
 ```
 
 ## Run