Performance testing

[buskamuza]

Check performance with new implementation, both with native Sodium and sodium_compat one.
See if we have performance tests that cover scenarios with encrypted data.

[aepod]

All MPT jmeter tests that are provided use checkmo as the payment method.
None of the other sections write data to customer or orders that I know of that have encrypted data.

It would not be hard to add some calls to save password or something, and be able to test this. But, I don't think you have anything out of the box that can do it in the MPT.

[buskamuza]

I think we should be good with one-time measurements. Not necessary to implement tests to run on every PR for this functionality.
cc @piotrekkaminski

[aepod]

I should be able to rig up a test from MPT if you want, I would guess the easiest test of this is to use password save, which will use this function. Once you get a good baseline test for how many times you can set a password per minute, run the same test before after.. this should at least give you a good comparison. Let me know if you think another way of testing this would be better?