Minor fixes, #523 followup

[kevinjqliu]

Follow up to #523

Remove print in test (left it in accidentally, saw it was removed in #559)
Call .as_arrow() once
Uncomment test for sqlite

[HonahX]

@kevinjqliu Thanks for fixing this. Do you mind cleaning up the other 2 "prints" in test_reads.py and test_writes.py too? (#562 )

[kevinjqliu]

oops looks like you already had a PR. I just removed all the prints

[HonahX]

Thanks @kevinjqliu ! I will merge this when tests pass and close the other one :).

[HonahX]

OOPs, sorry I forgot that the same pattern also exists in table.overwrite(). Seems we need another PR to update that to call arrow() once, too.