add err check and retries for elastic_fleet_integration_create

salt/elasticfleet/tools/sbin/so-elastic-fleet-integration-policy-elastic-defend

@@ -18,6 +18,9 @@ do
       elastic_fleet_integration_policy_upgrade "$INTEGRATION_ID"
   else
     printf "\n\nIntegration does not exist - Creating integration\n"
-    elastic_fleet_integration_create "@$INTEGRATION"
+    if ! elastic_fleet_integration_create "@$INTEGRATION"; then
+        echo -e "\nFailed to create integration for ${INTEGRATION##*/}"
+        exit 1
+    fi
   fi
 done