roachtest: create roachtest testing sql stats with a high fingerprint cardinality workload

We should create a roachtest that runs the `sqlstats` workload to test the impacts of the sql stats collection process when it is required to operate at its limits:
Things to verify / test:
* What is the impact on rest of system of storing and flushing the maximum number of statement and transaction fingerprints
* Flush operation should complete in reasonable times - data should be persisted at a consistent rate
* The system should operate normally when throttling inserting more stats into in-memory containers - i.e. throttling should not trigger any special / edge case behaviours in resource consumption

Jira issue: CRDB-38602

Epic CRDB-39776