feat: have ak.to_parquet create parent directories when necessary

[rpsimeon34]

Address #3770

[ikrommyd]

I would argue that it is a bit strange if we only do this for parquet. The other ak.to_* functions do not create parent directories either. Should we maybe do this for all functions that dump to disk @ianna?

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.64%. Comparing base (b749e49) to head (545405b).
⚠️ Report is 500 commits behind head on main.

Additional details and impacted files

Files with missing lines	Coverage Δ
src/awkward/operations/ak_to_parquet.py	64.96% <100.00%> (+2.94%)	⬆️

... and 200 files with indirect coverage changes

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[github-actions]

The documentation preview is ready to be viewed at http://preview.awkward-array.org.s3-website.us-east-1.amazonaws.com/PR3771