Environment: Stage

Slack thread: https://redhat-internal.slack.com/archives/C01F7QFNATC/p1688569843455359

A complete and detailed explanation is in the Slack thread above.

Tally ROSA API does not return the summed value when there is no daily usage. This is valid for instances and cores.

Reproducer steps:

Assuming you will reproduce this on July 05.

1 . Add metering events for July 03 of 2.2 cores and 3.99 instances hours for ROSA product

2. Request data for monthly usage for ROSA Instances hours and Cores
tally/products/rosa/Instance-hours?ending=2023-07-31T23:59:59.999Z&granularity=Daily&beginning=2023-07-01T00:00:00.000Z&use_running_totals_format=true&billing_category=prepaid

and 

tally/products/rosa/Cores?ending=2023-07-31T23:59:59.999Z&granularity=Daily&beginning=2023-07-01T00:00:00.000Z&use_running_totals_format=true&billing_category=on-demand

3. See the API response with zero for days 04 and 05 of July when the correct response should be 3 for cores and 4 for instances for both days.

4. Add metering events for the current day, July 05, of 4.4 cores and 7.09 instances hours for ROSA product

5. Request API for both params again, and Now the API responds with the sum of day 03 and 05 of July for day 05 response, but day 04 does not change. 

This seems related to the API not summing when there is no data for a day(a day with no data skips the summing logic).