[feature](Nereids) support select distinct with aggregate

fe/fe-core/src/main/java/org/apache/doris/nereids/parser/LogicalPlanBuilder.java

@@ -2896,10 +2896,6 @@ private LogicalPlan withSelectQuerySpecification(
             SelectColumnClauseContext selectColumnCtx = selectClause.selectColumnClause();
             LogicalPlan aggregate = withAggregate(filter, selectColumnCtx, aggClause);
             boolean isDistinct = (selectClause.DISTINCT() != null);
-            if (isDistinct && aggregate instanceof Aggregate) {
-                throw new ParseException("cannot combine SELECT DISTINCT with aggregate functions or GROUP BY",
-                        selectClause);
-            }
             if (!(aggregate instanceof Aggregate) && havingClause.isPresent()) {
                 // create a project node for pattern match of ProjectToGlobalAggregate rule
                 // then ProjectToGlobalAggregate rule can insert agg node as LogicalHaving node's child

regression-test/suites/nereids_syntax_p0/window_function.groovy

@@ -192,4 +192,13 @@ suite("window_function") {
           left join adj_nullable_2 on c1 = c4
         where c6 is not null;
     """
+
+    // distinct with window
+    sql """
+        SELECT
+              DISTINCT dt,
+              count(dt2) over (partition by dt) as num
+              from
+              (select 1 as dt,2 as dt2)t
+        group by dt,dt2"""
 }