Unquarantines the spec to have it start running in Staging again

What does this MR do and why?

I haven't been able to reproduce the flaky failures with this spec when I run it against Staging manually. Tried to flag down what caused the 404 last week but the logs in Kibana are already gone so I can't tell what the 404 was about. Unquarantining the spec so I can flag it down when it fails again on Staging. #340885 (comment 839391536)

Related: #340885 (closed)

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