Turn off failure issue auto assign

What does this MR do and why?

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Per discussion https://gitlab.slack.com/archives/C064M4S0FU5/p1759880104881879?thread_ts=1759500803.778479&cid=C064M4S0FU5, turning test failures' auto assign issue to SETs functionality off. I'm not touching find_set_dri and other similar features in case we can repurpose them per gitlab-org/quality&154

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