Fix window rewrite aggregate call type inference

Author: vldpyatkov

modules/calcite/src/main/java/org/apache/ignite/internal/processors/query/calcite/rule/logical/IgniteLogicalWindowRewriteRule.java

@@ -300,11 +300,6 @@ private static AggregateCall toAggregateCall(Window.RexWinAggCall winAggCall) {
 
         SqlAggFunction agg = (SqlAggFunction)winAggCall.getOperator();
 
-        // Use the type resolved for the window call itself. It already includes correct
-        // nullability (for example AVG over constant expressions), while direct inference
-        // from operands can return a different nullability and break AggregateCall checks.
-        RelDataType inferredType = winAggCall.getType();
-
         return AggregateCall.create(
             agg,
             winAggCall.distinct,
@@ -313,7 +308,7 @@ private static AggregateCall toAggregateCall(Window.RexWinAggCall winAggCall) {
             argList,
             -1,
             RelCollations.EMPTY,
-            inferredType,
+            null,
             null
         );
     }