[v10.3.x] Alerting docs: recovery threshold (#81239)

Alerting docs: recovery threshold (#81069)

* Alerting docs: recovery threshold

* ran prettier

* Adds note that only available in oss

* ran prettier

(cherry picked from commit 030a68bbf7)

Co-authored-by: brendamuir <100768211+brendamuir@users.noreply.github.com>

docs/sources/alerting/alerting-rules/create-grafana-managed-rule.md

@@ -71,6 +71,7 @@ Define a query to get the data you want to measure and a condition that needs to
    All alert rules are managed by Grafana by default. If you want to switch to a data source-managed alert rule, click **Switch to data source-managed alert rule**.
 
 1. Add one or more [expressions][expression-queries].
+
    a. For each expression, select either **Classic condition** to create a single alert rule, or choose from the **Math**, **Reduce**, and **Resample** options to generate separate alert for each series.
 
    {{% admonition type="note" %}}
@@ -79,6 +80,14 @@ Define a query to get the data you want to measure and a condition that needs to
 
    b. Click **Preview** to verify that the expression is successful.
 
+{{% admonition type="note" %}}
+The recovery threshold feature is currently only available in OSS.
+{{% /admonition %}}
+
+1. To add a recovery threshold, turn the **Custom recovery threshold** toggle on and fill in a value for when your alert rule should stop firing.
+
+   You can only add one recovery threshold in a query and it must be the alert condition.
+
 1. Click **Set as alert condition** on the query or expression you want to set as your alert condition.
 
 ## Set alert evaluation behavior