Bug 21112: Re-indent staff client cart template

This patch reindents the template for the staff client cart, basket.tt

- Trailing spaces removed
- Indentation changed to a consistent 4 spaces
- Markup indentation made more consistent

To test, apply the patch and add multiple items to the cart in the staff
client.

View the cart and confirm that it looks as it should both in the "brief"
and "more details" views.

HTML validation before and after the patch should return the same
results.

Signed-off-by: DEVINIM <kohadevinim@devinim.com.tr>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>