`test_insert_failure_doesnt_report_success` test in `test/cluster/dtest/audit_test.py`
has an insert statement that is expected to fail. Dtest environment uses
`FlakyRetryPolicy`, which has `max_retries = 5`. 1 initial fail and 5 retry fails
means we expect 6 error audit logs.
The test failed because `create keyspace ks` failed once, then succeeded on retry.
It allowed the test to proceed properly, but the last part of the test that expects
exactly 6 failed queries actually had 7.
The goal of this patch is to make sure there are exactly 6 = 1 + `max_retries` failed
queries, counting only the query expected to fail. If other queries fail with
successful retry, it's fine. If other queries fail without successful retry, the test
will fail, as it should in such situations. They are not related to this expected
failed insert statement.
Fixes#27322Closesscylladb/scylladb#27378
f545ed37bc