Cts test fix for shortcode 48000

TIM Italy has requested that shortcode 48000 to be flagged as free.
This changes the cts SmsUsageMonitorShortCodeTest so that it
handles 48000 as a free shortcode.

Change-Id: I3c446cbbd94150a45310c1d518f394eed6ee58e8
(cherry picked from commit 3f3336aa5993b6d1ad2f8d578010785409ab3e15)
1 file changed