tests: update i18n tests

Signed-off-by: David Aguilar <davvid@gmail.com>
testwrap: adjust algorithm to drop leading whitespace

It's common to end a sentence with period-double-space.
The original algorithm would wrap and place a double-space
at the start of the next line.

Adjust it to drop leading spaces and add a test to ensure
the correct behavior correct.

Signed-off-by: David Aguilar <davvid@gmail.com>