Add support for filtering map attributes using regex operator

[sarthak77]

Based on this discussion, add support for filtering using regex operator.

eg. Working pinot query :

select * from spanEventView
where start_time_millis > 1628187491000 and start_time_millis < 1638188391000
and tags__KEYS = 'span.kind'
and mapValue(tags__KEYS, 'span.kind', tags__VALUES) != ''  
and REGEXP_LIKE(mapValue(tags__KEYS, 'span.kind', tags__VALUES), '^client*')
limit 10