Span first Celery integration sometimes doesn't set the name well

[vgrozdanic]

Example trace: https://span-first-test.sentry.io/explore/traces/trace/189b87cfd2cf4800856857f4b57d41bb/?aggregateField=%7B%22groupBy%22%3A%22%22%7D&aggregateField=%7B%22yAxes%22%3A%5B%22count%28span.duration%29%22%5D%7D&extrapolate=0&field=id&field=span.name&field=span.description&field=span.duration&field=transaction&field=timestamp&field=previous_trace&mode=samples&node=span-8d36933eb527151e&project=4510941608083552&query=&source=traces&statsPeriod=1h&targetId=b93b1aa8fb607a3a&timestamp=1771961070

This happens only for some tasks, some of them have proper name set

[linear]

PY-2096

[sentrivana]

At least one source of these will be fixed with ec7e2d7. Let's see if more remain after we've tried this out.