Add regression tests for integer overflows

[h-mayorquin]

We have solved many of these but we did not write regression tests for them. This issue should serve as a list of those PRs so we can add regression tests later. This is important because those errors are easy to miss (it just changing lists to numpy arrays!) so I think it is good to have regression tests here:

List:

• Fix integer overflow in parallel computing #3426
• Fix integer overflow of the total sample number when concatenating long recordings #3388

There were some more related to concatenation that I would fetch later.