We modify the logic to make sure that all of the keyspaces that the test
creates are RF-rack-valid. For that, we distribute the nodes across two
DCs and as many racks as the provided replication factor.
That may have an effect on the load balancing logic, but since this is
a performance test and since tablet load balancing is still taking place,
it should be acceptable.
This commit also finishes work in adjusting perf tests to pass with
the `rf_rack_valid_keyspaces` configuration option enabled. The remaining
tests either don't attempt to create keyspaces or they already create
RF-rack-valid keyspaces.
We don't need to explicitly enable the configuration option. It's already
enabled by default by `cql_test_config`. The reason why we haven't run into
any issue because of that is that performance tests are not part of our CI.
Fixesscylladb/scylladb#25127Closesscylladb/scylladb#25728
(cherry picked from commit 789a4a1ce7)
Closesscylladb/scylladb#25922
3dac49c62f