Cherry-Pick bot gets parents wrong even if whole chain was staged together

Latest in a long list of examples¹:

https://codereview.qt-project.org/c/qt/qtbase/+/491064 has conflicts only because the bot didn't pick it onto https://codereview.qt-project.org/c/qt/qtbase/+/490980 where it belongs, even though both changes were staged together and integrated in the same round (https://testresults.qt.io/coin/integration/qt/qtbase/tasks/1694640704).

This is getting out of hand. I don't remember it being this bad before. It almost feels like the bot fails this 100% of the time these days when all the years before it would work.

¹ I don't know how to query Gerrit for all the past issues. If Gerrit wouldn't receive the merged SHA-1 in the end, overwriting the uploader, it would be owner:cherrypick_bot@qt-project.org uploader:marc.mutz@qt.io