Aggregation function window setting is ignored in monitoring check

__Steps to reproduce:__

1. create monitoring check with 1h schedule and 1m aggreation fn window for a metric that is reported frequently.

__Expected behavior:__
There should be about 60 statuses in the history per hour.

__Actual behavior:__
There is just 1 status per hour.

__Environment info:__
Influxdb 2.0-beta6

Reproduce the monitoring-check scenario described in the issue using a 1h schedule, a 1m aggregation window, and a frequently reported metric. Trace how aggregation-window settings affect status history, then verify that the history contains about 60 statuses per hour rather than one.

Written by the indexing model from the issue text.