[Cloud Security] fix 'show 1 alerts' bug (#191062)

## Summary

Using plural from `react-intl` in the Session View for `Show N alerts`
text

- part of https://github.com/elastic/security-team/issues/10316
- fixes https://github.com/elastic/kibana/issues/189880

x-pack/plugins/session_view/public/components/process_tree_alerts_filter/index.test.tsx

@@ -53,6 +53,19 @@ describe('ProcessTreeAlertsFiltersFilter component', () => {
       expect(filterCountStatus).toBeTruthy();
     });
 
+    it('should show pluralise correctly', async () => {
+      renderResult = mockedContext.render(
+        <ProcessTreeAlertsFilter {...props} totalAlertsCount={1} filteredAlertsCount={1} />
+      );
+
+      const filterCountStatus = renderResult.queryByTestId(
+        'sessionView:sessionViewAlertDetailsFilterStatus'
+      );
+
+      expect(filterCountStatus).toHaveTextContent('Showing 1 alert');
+      expect(filterCountStatus).toBeTruthy();
+    });
+
     it('should call onAlertEventCategorySelected with alert category when filter item is clicked ', () => {
       const mockAlertEventCategorySelectedEvent = jest.fn();
       renderResult = mockedContext.render(

x-pack/plugins/session_view/public/components/process_tree_alerts_filter/index.tsx

@@ -124,9 +124,10 @@ export const ProcessTreeAlertsFilter = ({
             {totalAlertsCount === filteredAlertsCount && (
               <FormattedMessage
                 id="xpack.sessionView.alertTotalCountStatusLabel"
-                defaultMessage="Showing {count} alerts"
+                defaultMessage="{count, plural, one {Showing <bold>#</bold> alert} other {Showing <bold>#</bold> alerts}}"
                 values={{
-                  count: <strong>{totalAlertsCount}</strong>,
+                  count: totalAlertsCount,
+                  bold: (str: string) => <strong>{str}</strong>,
                 }}
               />
             )}

x-pack/plugins/translations/translations/fr-FR.json

@@ -41491,7 +41491,6 @@
     "xpack.sessionView.alertFilteredCountStatusLabel": " Affichage de {count} alertes",
     "xpack.sessionView.alerts": "Alertes",
     "xpack.sessionView.alertsLoadMoreButton": "Charger plus d'alertes",
-    "xpack.sessionView.alertTotalCountStatusLabel": "Affichage de {count} alertes",
     "xpack.sessionView.backToInvestigatedAlert": "Retour à l'alerte examinée",
     "xpack.sessionView.blockedBadge": "Bloqué",
     "xpack.sessionView.childProcesses": "Processus enfants",

x-pack/plugins/translations/translations/ja-JP.json

@@ -41475,7 +41475,6 @@
     "xpack.sessionView.alertFilteredCountStatusLabel": " {count}件のアラートを表示しています",
     "xpack.sessionView.alerts": "アラート",
     "xpack.sessionView.alertsLoadMoreButton": "その他のアラートを読み込む",
-    "xpack.sessionView.alertTotalCountStatusLabel": "{count}件のアラートを表示しています",
     "xpack.sessionView.backToInvestigatedAlert": "調査されたアラートに戻る",
     "xpack.sessionView.blockedBadge": "ブロック",
     "xpack.sessionView.childProcesses": "子プロセス",

x-pack/plugins/translations/translations/zh-CN.json

@@ -41518,7 +41518,6 @@
     "xpack.sessionView.alertFilteredCountStatusLabel": " 正在显示 {count} 个告警",
     "xpack.sessionView.alerts": "告警",
     "xpack.sessionView.alertsLoadMoreButton": "加载更多告警",
-    "xpack.sessionView.alertTotalCountStatusLabel": "正在显示 {count} 个告警",
     "xpack.sessionView.backToInvestigatedAlert": "返回到已调查告警",
     "xpack.sessionView.blockedBadge": "已阻止",
     "xpack.sessionView.childProcesses": "子进程",