Switch `VecOfArrays` for RecursiveArrayTools's `VectorOfArray`

[benegee]

Recent updates made RecursiveArrayTools's VectorOfArray do the right thing when used with Adapt.jl. Hence we can avoid using our own VecOfArrays.

[github-actions[bot]]

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[codecov[bot]]

Codecov Report

:white_check_mark: All modified and coverable lines are covered by tests. :white_check_mark: Project coverage is 96.85%. Comparing base (edde724) to head (fe2780d).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2491      +/-   ##
==========================================
+ Coverage   96.83%   96.85%   +0.02%     
==========================================
  Files         550      549       -1     
  Lines       43455    43437      -18     
==========================================
- Hits        42079    42070       -9     
+ Misses       1376     1367       -9     

Flag	Coverage Δ
unittests	96.85% <100.00%> (+0.02%)	:arrow_up:

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