58dc414912
We rewrite the test to avoid flakiness. Instead of looking at the metrics, we make a trade-off and start depending on a less reliable mechanism -- logs. We grep all relevant messages printed by Scylla in TRACE mode and make sure that they were all printed from a context using the streaming scheduling group. Although it's a "less proper" way of testing, it should be much more dependable and avoid flakiness. Fixes scylladb/scylladb#25957 Closes scylladb/scylladb#26656