Another estimateMemoryUsageBytes fix

Author: jan-elastic

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ml/action/StartTrainedModelDeploymentAction.java

@@ -799,6 +799,9 @@ public static long estimateMemoryUsageBytes(
         long perAllocationMemoryBytes,
         int numberOfAllocations
     ) {
+        if (numberOfAllocations == 0) {
+            return 0;
+        }
         // While loading the model in the process we need twice the model size.
 
         // 1. If ELSER v1 or v2 then 2004MB