Incorrect result returned by INTERSECT

[YuanchengJiang]

Describe the bug

Buggy query:

(SELECT count(1) FROM telemetry as T1 CROSS JOIN telemetry as T2 WHERE T2.created=NOW() AND T2.created='2023-04-14 19:11:51+00' ) INTERSECT (SELECT count(1) FROM telemetry as T1 JOIN telemetry as T2 on T1.created=T2.created JOIN telemetry as T3 ON T2.created=T3.created WHERE T3.created<NOW() )

The buggy query is a bit complex (I have tried to simplify it but it does not happen in simple cases):
The first half is SELECT count(1) FROM telemetry as T1 CROSS JOIN telemetry as T2 WHERE T2.created=NOW() AND T2.created='2023-04-14 19:11:51+00' where the predicate is always False, so the subquery result is 0.
The second half is SELECT count(1) FROM telemetry as T1 JOIN telemetry as T2 on T1.created=T2.created JOIN telemetry as T3 ON T2.created=T3.created WHERE T3.created<NOW() where the predicate is always True, so the subquery result is greater than 0.
The INTERSECT should return an empty result: [], however, it returns [(0,)]
Replacing the first half with (SELECT 0) or the second half with (SELCT 100) does not have this issue.

To reproduce

(SELECT count(1) FROM telemetry as T1 CROSS JOIN telemetry as T2 WHERE T2.created=NOW() AND T2.created='2023-04-14 19:11:51+00' ) INTERSECT (SELECT count(1) FROM telemetry as T1 JOIN telemetry as T2 on T1.created=T2.created JOIN telemetry as T3 ON T2.created=T3.created WHERE T3.created<NOW() )

Expected Behavior

The INTERSECT should return an empty result: [], however, it returns [(0,)]

Environment

- **QuestDB version**: v7.2.1
- **OS**: ubuntu 20.04

Additional context

No response