Description of problem:
not operator on string in the select clause is returning the same string instead of boolean value 

executing query-65: select ( not 'Ix8vrSP6MNFNMnjLG0XB' ) from s3object;
Stats
{'Details': {'BytesProcessed': 145,
             'BytesReturned': 63,
             'BytesScanned': 145}}
End
{}
Ix8vrSP6MNFNMnjLG0XB
Ix8vrSP6MNFNMnjLG0XB
Ix8vrSP6MNFNMnjLG0XB



Version-Release number of selected component (if applicable):
ceph version 18.2.0-128.el9cp

How reproducible:
always

Steps to Reproduce:
1.deploy rhcs7.0 cluster with rgw daemon
2.upload an s3select object
3.execute the above query and verify the results are correct

Actual results:
not operator on string in the select clause is returning the same string instead of boolean value 

Expected results:
expected boolean value as result

Additional info:
query result validation script: https://docs.google.com/document/d/1UT8zTizHHVTWYmfXZdgChYJh7rT4bovOJmsecS86qYU/edit?usp=sharing