[Enhancement][ESS] Only open or acknowledged alerts are considered fo…

…r alert suppression (#5122)

* First draft

* Update docs/detections/alert-suppression.asciidoc

(cherry picked from commit 9d4209c)

docs/detections/alert-suppression.asciidoc

@@ -47,6 +47,8 @@ TIP: Use the *Rule preview* before saving the rule to visualize how alert suppre
 
 The {security-app} displays several indicators of whether a detection alert was created with alert suppression enabled, and how many duplicate alerts were suppressed.
 
+IMPORTANT: After an alert is moved to the `Closed` status, it will no longer suppress new alerts. To prevent interruptions or unexpected changes in suppression, avoid closing alerts before the suppression interval ends.
+
 * *Alerts* table — Icon in the *Rule* column. Hover to display the number of suppressed alerts:
 +
 [role="screenshot"]