Getting rid of parked_car(s)

BUR #24629 has been approved by @nonamethanks.

mass update parked_car -> car -parked_car

I don't think this has a significant value. It just shows an idle car.
Bumped for moderation.

This bulk update request is pending automatic rejection in 5 days.

This bulk update request has been rejected because it was not approved within 45 days.

The bulk update request #24629 (forum #274068) has been rejected by @DanbooruBot.

Is there really a meaningful difference in parked vs motion for non-animated posts?

The bulk update request #24629 (forum #274068) has been approved by @nonamethanks.