[multistage] Investigate why some aliases are removed by Apache Calcite for window functions

For some of the window function queries the aliases are removed. Need to look into why. Opening this ticket to track this work.

E.g.

```
"sql": "EXPLAIN PLAN FOR SELECT a.col1 AS value1, ROW_NUMBER() OVER(ORDER BY a.col2) AS row_number FROM a",

"Execution Plan",
"\nLogicalProject(col1=[$0], $1=[$2])",
"\n LogicalWindow(window#0=[window(order by [1] rows between UNBOUNDED PRECEDING and CURRENT ROW aggs [ROW_NUMBER()])])",
"\n PinotLogicalSortExchange(distribution=[hash], collation=[[1]], isSortOnSender=[false], isSortOnReceiver=[true])",
"\n LogicalProject(col1=[$0], col2=[$1])",
"\n LogicalTableScan(table=[[a]])",
"\n"
```

cc @siddharthteotia