message: Monitoring: Hide kebab menu for silenced alerts in Active Alerts list
  In the Active Alerts list (on the Rule details page), the only kebab
  menu action is "Silence Alert". However, we don't want to show that
  action for alerts that are already silenced, so remove the menu
  completely in this case.
diff: @@ -287,7 +287,7 @@ const ActiveAlerts = ({alerts, ruleID}) => <div className="co-m-table-grid co-m-
  <div className="col-sm-2 hidden-xs"><Timestamp timestamp={a.activeAt} /></div>
  <div className="col-sm-2 col-xs-3"><AlertState state={a.state} /></div>
  <div className="col-sm-2 col-xs-3 co-break-word">{a.value}</div>
  - <div className="dropdown-kebab-pf"><Kebab options={[silenceAlert(a)]} /></div>
  + {a.state !== AlertStates.Silenced && <div className="dropdown-kebab-pf"><Kebab options={[silenceAlert(a)]} /></div>}
  </ResourceRow>)}
  </div>
  </div>;
  