clean up .ansible dir left behind in ~/

This issue was originally opened by @SwampDragons as hashicorp/packer#9436. It was migrated here as a result of the Packer plugin split. The original body of the issue is below.

When the ansible provisioner runs, it leaves behind a .ansible folder in the ansible user's homedir. It would be cool if we could clean that directory up so that the image is left in a more pristine state.

See comment https://github.com/hashicorp/packer/issues/9118#issuecomment-644529777 for more details.