Convert h1 to h2 (2.6)

docs/reference-guides/system-tools.md

@@ -8,11 +8,11 @@ System Tools has been deprecated since June 2022.
 
 :::
 
-# Logs
+## Logs
 
 Please use [logs-collector](https://github.com/rancherlabs/support-tools/tree/master/collection/rancher/v2.x/logs-collector) to collect logs from your cluster.
 
-# Stats
+## Stats
 
 If you want to replicate the stats command, you can run the following command on your cluster nodes:
 
@@ -26,6 +26,6 @@ This command below requires the package `sysstat` on the cluster node.
 /usr/bin/sar -u -r -F 1 1
 ```
 
-# Remove
+## Remove
 
 Please use the [Rancher Cleanup](https://github.com/rancher/rancher-cleanup) tool.