Work around paginator flaw by querying issues in descending order

[gnilrets]

Description of change

Resolves #109 by querying issue data in descending update order.

Manual QA steps

• I added more logging to manually demonstrate that a record can be skipped if another record is updated on a page that has been previously queried. After this change, we can get duplicates in this situation, which may be removed by downstream singer targets.

Risks

• Dupes may not always be treated gracefully in targets.

Rollback steps

• revert this branch

[singer-bot]

Hi @gnilrets, thanks for your contribution!

In order for us to evaluate and accept your PR, we ask that you sign a contribution license agreement. It's all electronic and will take just minutes.