refactor: use nplike.asarray

[agoose77]

The work to move to an array-API inspired UX requires that we drop array and asarray distinctions; now asarray takes a copy parameter, and drops the order parameter.

I'm gradually dropping nplike usage in our tests, where appropriate; we should probably focus on testing L1 and L2, not L3.

[codecov]

Codecov Report

Merging #2134 (ab59f6e) into main (3a0d3c9) will increase coverage by 0.01%.
The diff coverage is 81.63%.

Additional details and impacted files

Impacted Files	Coverage Δ
src/awkward/_connect/jax/reducers.py	82.14% <ø> (ø)
src/awkward/_connect/numba/layout.py	83.37% <ø> (-0.05%)	⬇️
src/awkward/_reducers.py	88.69% <0.00%> (ø)
src/awkward/contents/unionarray.py	84.98% <0.00%> (ø)
src/awkward/operations/ak_concatenate.py	96.03% <ø> (ø)
src/awkward/operations/ak_fill_none.py	95.00% <ø> (ø)
src/awkward/operations/ak_unflatten.py	95.45% <ø> (ø)
src/awkward/contents/indexedoptionarray.py	88.67% <50.00%> (ø)
src/awkward/operations/ak_flatten.py	92.30% <50.00%> (ø)
src/awkward/_nplikes.py	64.77% <62.50%> (-0.36%)	⬇️
... and 16 more

[jpivarski]

Looks good! (For posterity: we talked about this in our weekly Zoom meeting. The functionality of asarray and array is being combined in Array-API, so we're following the same pattern in our nplikes for future-proofing.)