Tests: Fix edge case in InternalSimpleValueTests (#26084)

When value is NaN, the mutate function might return a new instance that is
equal to the original one.

* Add same fix for InternalDerivativeTests

core/src/test/java/org/elasticsearch/search/aggregations/pipeline/InternalSimpleValueTests.java

@@ -81,7 +81,11 @@ public class InternalSimpleValueTests extends InternalAggregationTestCase<Intern
             name += randomAlphaOfLength(5);
             break;
         case 1:
-            value += between(1, 100);
+            if (Double.isFinite(value)) {
+                value += between(1, 100);
+            } else {
+                value = randomDoubleBetween(0, 100000, true);
+            }
             break;
         case 2:
             if (metaData == null) {

core/src/test/java/org/elasticsearch/search/aggregations/pipeline/derivative/InternalDerivativeTests.java

@@ -84,7 +84,11 @@ public class InternalDerivativeTests extends InternalAggregationTestCase<Interna
             name += randomAlphaOfLength(5);
             break;
         case 1:
-            value += between(1, 100);
+            if (Double.isFinite(value)) {
+                value += between(1, 100);
+            } else {
+                value = randomDoubleBetween(0, 100000, true);
+            }
             break;
         case 2:
             normalizationFactor += between(1, 100);