[scheduler] Fix periodically failing DataTransferSessionWrongChecksumMigration test
Description
The unit test was operating on a wrong assumption that the order in which archive requests are enqueued is always the same as the order in which they end up in the queue. Given the async nature of the objectstore, this is not always the case. This change fixes that.
It also removes the fseq terminology, which is incorrectly used in the test.
Checklist
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Documentation reflects the changes made. -
Merge Request title is clear, concise, and suitable as a changelog entry. See our contributing docs
References
Closes #1302 (closed)