Geo QA: Test replication and verification of issue attachments
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## Problem
Geo has a QA test for issue attachments which checks that a user can view the attachment on the secondary site. This only tests secondary proxying behavior. It does not test Geo replication or verification.
## Proposal
Test replication and verification of issue attachments in Geo QA tests by checking that the secondary site reports that the issue attachment became synced and verified.
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