fix: add test case

tests/script/tsim/query/interval.sim

@@ -206,6 +206,19 @@ if $desc_rows != $asc_rows then
   return -1
 endi
 
+print ================= step11
+
+sql create database if not exists test0828
+sql use test0828
+sql create stable st (ts timestamp, c2 int) tags(tg int)
+sql insert into ct1 using st tags(1) values('2021-08-01', 0)
+sql insert into ct2 using st tags(2) values('2022-08-01', 1)
+sql select _wstart, _wend, count(*) from st where ts>='2021-01-01' and ts < now interval(1n) fill(value, 0) order by _wstart desc
+print $rows
+if $rows != 32 then
+  return -1
+endi
+sql drop database test0828
 print =============== clear
 #sql drop database $db
 #sql select * from information_schema.ins_databases