fix: support non int64 index in ListArray's pad_none

[agoose77]

This PR does two things:

1. Changes dtypes of a kernel call (awkward_ListArray_rpad_axis1)
   The kernel is written with the following template signature

   T* toindex,
   const C* fromstarts,
   const C* fromstops,
   C* tostarts,
   C* tostops,

   i.e. starts and tostarts are expected to have the same dtypes. We can rewrite the kernel call site to ensure that this is true. This bug was observed after reading data from Arrow with 32-bit indices.
2. When using pad_none, we shouldn't copy the parameters of the content to the new mask node; this duplicates parameters, and doesn't consider the rules about e.g. whether the content is allowed to possess such parameters.¹

Footnotes

1. this remains a general class of problem IIRC with broadcasting that we'll need to work on. However, this fix is also correct; we don't want duplicate parameters. ↩

[codecov]

Codecov Report

Merging #2634 (746cbdb) into main (e2eb69a) will not change coverage.
The diff coverage is 100.00%.

Additional details and impacted files

Files Changed	Coverage Δ
src/awkward/contents/content.py	76.16% <100.00%> (ø)
src/awkward/contents/listarray.py	88.60% <100.00%> (ø)

[jpivarski]

Good catch; we use 64-bit so often that it's easy to miss cases that should work for 32-bit as well.

I'll merge it.