chore(deps): update prom/alertmanager docker tag to v0.28.1 (main) (#16633)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

production/docker/docker-compose.yaml

@@ -180,7 +180,7 @@ services:
 
   # alertmanager to enable receiving alerts
   alertmanager:
-    image: prom/alertmanager:v0.28.0
+    image: prom/alertmanager:v0.28.1
     restart: unless-stopped
     ports:
       - "9093:9093"