Fix: handle null key in IterativeBinarySearch (#7365)

* Fix: handle null key in IterativeBinarySearch

* style: fix indentation in IterativeBinarySearch

* style: fix indentation in IterativeBinarySearch

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Co-authored-by: Kadambari <kadambari179@gmail.com>

Author: kadambari25

src/main/java/com/thealgorithms/searches/IterativeBinarySearch.java

@@ -33,7 +33,7 @@ public final class IterativeBinarySearch implements SearchAlgorithm {
      */
     @Override
     public <T extends Comparable<T>> int find(T[] array, T key) {
-        if (array == null || array.length == 0) {
+        if (array == null || array.length == 0 || key == null) {
             return -1;
         }