Increase client-side QPS and Burst

[nguyenvancaonguyen]

What would you like to be added:
Increase client-side QPS and Burst

Why is this needed:
We hit throttling limit event with parallel: 1 option and it make the test run slower

[porridge]

@nguyenvancaonguyen can you please provide some logs or (even better) a minimal repro?
If we're hitting limits when using a cached client I wonder if we should rethink what requests we're making instead of blindly bumping them... 🤔