Use date32 for pyarrow date

[alippai]

• closes #xxxx (Replace xxxx with the GitHub issue number)
• Tests added and passed if fixing a bug or adding a new feature
• All code checks passed.
• Added type annotations to new arguments/methods/functions.
• Added an entry in the latest doc/source/whatsnew/vX.X.X.rst file if fixing a bug or adding a new feature.

[mroeschke]

I don't think this necessarily should unequivocally be date32. There may be a use case for storing with increased precision.

[alippai]

@mroeschke the precision is always the same, it's unexpected to store non-fullday value in pa.date64 and date64 is always milliseconds: https://lists.apache.org/thread/q036r1q3cw5ysn3zkpvljx3s9ho18419

The only gain of using that type is the cheaper conversion for frameworks / languages using millisecond based timestamps, but it's slower and uses more memory.

[lumberbot-app]

Owee, I'm MrMeeseeks, Look at me.

There seem to be a conflict, please backport manually. Here are approximate instructions:

1. Checkout backport branch and update it.

git checkout 2.0.x
git pull

2. Cherry pick the first parent branch of the this PR on top of the older branch:

git cherry-pick -x -m1 4d1c994da1e9815c87db2cd48a3286b077f2f7fe

3. You will likely have some merge/cherry-pick conflict here, fix them and commit:

git commit -am 'Backport PR #52332: Use date32 for pyarrow date'

4. Push to a named branch:

git push YOURFORK 2.0.x:auto-backport-of-pr-52332-on-2.0.x

5. Create a PR against branch 2.0.x, I would have named this PR:

"Backport PR #52332 on branch 2.0.x (Use date32 for pyarrow date)"

And apply the correct labels and milestones.

Congratulations — you did some good work! Hopefully your backport PR will be tested by the continuous integration and merged soon!

Remember to remove the Still Needs Manual Backport label once the PR gets merged.

If these instructions are inaccurate, feel free to suggest an improvement.

[mroeschke]

Thanks for the explanation @alippai

[alippai]

Thanks for the swift merge and backport @mroeschke