Docs: Add documentation for new enterprise caching enhancement (per-panel TTL) (#62838)

* add documentation for new per-panel caching TTL feature

* update image url, use figure

docs/sources/administration/data-source-management/index.md

@@ -154,6 +154,10 @@ By default, data source queries are not cached. To enable query caching for a si
 1. Press the Enable button.
 1. (Optional) Choose custom TTLs for the data source's queries and resources caching. If you skip this step, then Grafana uses the default TTL.
 
+You can optionally override a data source's configured TTL for individual dashboard panels. This can be be useful when you have queries whose results change more or less often than the configured TTL. In the Edit Panel view, select the caching-enabled data source, expand the Query options, and enter your the TTL in milliseconds.
+
+{{< figure max-width="500px" src="/media/docs/grafana/per-panel-cache-ttl-9-4.png" caption="Set Cache TTL for a single panel" >}}
+
 > **Note:** If query caching is enabled and the Cache tab is not visible in a data source's settings, then query caching is not available for that data source.
 
 To configure global settings for query caching, refer to the [Query caching section of Enterprise Configuration]({{< relref "../../setup-grafana/configure-grafana/enterprise-configuration/#caching" >}}).