[FEATURE] Support pushdown `collect/array_agg` aggregation

[LantaoJin]

Is your feature request related to a problem?
#5025 introduces a new Calcite Aggregation COLLECT:
LogicalAggregate(group=[{0, 1}], age=[COLLECT($2) FILTER $3])
or
LogicalAggregate(group=[{0, 1}], packets_str=[ARRAY_AGG($2) FILTER $3])

Currently, PPL doesn't support pushdown a COLLECT aggregation to DSL, instead, it will be planned to EnumerableAggregate(group=[{0, 1}], age=[COLLECT($2) FILTER $3]).
or
EnumerableAggregate(group=[{0, 1}], packets_str=[ARRAY_AGG($2) FILTER $3])

What solution would you like?
Pushdown Aggregation COLLECT to TopHits aggregation.