YahooJapanReport downloads performance report even when a campaign has 0 performance

Test Steps:

1. Run yahoojapanreport for a campaign that does not have performance data for the particular date.
2. Check staging.yahooJAdmax table to view performance data.

Actual Result:
For a date when campaign does not have performance data, yahoojapanreport.sh download 0 as entries and feeds it into staging.yahooJAdmax table.

Example:
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Expected Result:
We should not be downloading reports from YJ when the performance data for a campaign is 0 for a particular date. This will allow us to improve the performance of the process and avoid downloading unwanted reports.