Missing WSCG check for ExistenceJoin

[jackylee-ch]

Describe the bug
We do a WSCG check in ColumnarShuffledHashJoinExec. But only check the condition, not leftKeys and rightKeys check.
For ExsitingJoin, the condition is null, and there are only leftKeys and rightKeys, which leads to function is currently not supported in WSCG.

To Reproduce

select * from table as t1 where concat(t1.a, "_", t1.b) in (select concat(t2.a, "_", t2.b) from table as t2)

Expected behavior
No Exception thrown and using WSCG if function doesn't support WSCG.

Additional context
None

[PHILO-HE]

Fixed.