This patch adds a regression test for verifying that queued
SMS messages meant for patrons who have no SMS alert number
set are marked as failed after the first attempt to send them.
To test:
[1] Run prove -v t/db_dependent/Letters.t. The fourth
test should.
[2] Apply the main patch and run t/db_dependent/Letters.t
again. This time, all tests should pass.
Signed-off-by: Galen Charlton <gmc@esilibrary.com>
