Tune Resource Limits for Performance verse Stability trade-off

We are introducing more resource constraints into KV to ensure resources utilisation and performance can be maintained.

For example in 7.1 we introduced the checkpoint quota - (MB-46827) and in 7.6.0 we introduced the readyQ limit (MB-57847) as well as disabled the max_checkpoints hard limit. This resulted in a change in performance behaviour - see MB-61246.

We need to:
1) Review the KV Tests run by the Performance Team, (and displayed in Showfast), and potentially develop / request additional (or alternative) tests and measures.
2) Establish an understanding of how the test results change as we modify the resource controls.
3) Set the controls to the values the provide the best trade-off between peak performance and stable behaviour.