[Cloud Security] fix the alert severity order (elastic#215813)

## Summary

Summarize your PR. If it involves visual changes include a screenshot or
gif.

Alert status Order was showing Low to High rather the showing the
highest status of severity to the lowest severity.
This PR removes the reverse and shows severity from Critical to Low. I
applied ranking order for critical to low to address the sort order

<img width="664" alt="image"
src="https://github.com/user-attachments/assets/2e0f4974-ea08-4bc4-ae1c-53b0c0f53561"
/>
<img width="408" alt="image"
src="https://github.com/user-attachments/assets/77db4442-53eb-44b5-a2d1-8dbbf1858dff"
/>

<img width="628" alt="image"
src="https://github.com/user-attachments/assets/947e8cc2-989b-4b9c-bffe-97ab2e15309d"
/>

Author: Omolola-Akinleye

x-pack/solutions/security/plugins/security_solution/public/cloud_security_posture/components/alerts/alerts_preview.tsx

@@ -74,6 +74,12 @@ export const AlertsPreview = ({
   const { euiTheme } = useEuiTheme();
 
   const severityMap = new Map<string, number>();
+  const severityRank: Record<string, number> = {
+    critical: 4,
+    high: 3,
+    medium: 2,
+    low: 1,
+  };
 
   (Object.keys(alertsData || {}) as AlertsByStatus[]).forEach((status) => {
     if (alertsData?.[status]?.severities) {
@@ -84,11 +90,12 @@ export const AlertsPreview = ({
     }
   });
 
-  const alertStats = Array.from(severityMap, ([key, count]) => ({
+  const alertStats = Array.from(severityMap, ([key, count]: [string, number]) => ({
     key: capitalize(key),
     count,
     color: getSeverityColor(key, euiTheme),
-  }));
+    sort: severityRank[key.toLowerCase()] || 0,
+  })).sort((a, b) => b.sort - a.sort);
 
   const totalAlertsCount = alertStats.reduce((total, item) => total + item.count, 0);
 
@@ -145,7 +152,7 @@ export const AlertsPreview = ({
             <EuiFlexItem>
               <EuiSpacer />
               <DistributionBar
-                stats={alertStats.reverse()}
+                stats={alertStats}
                 data-test-subj="AlertsPreviewDistributionBarTestId"
               />
             </EuiFlexItem>