TT#37257 Remove full path from shell trace debug mode

Switch from:
> +10:43:04 (/usr/sbin/ngcp-status:10): main():  export LC_ALL=C.UTF-8
to:
> +10:43:04 (ngcp-status:10): main():  export LC_ALL=C.UTF-8

Since we have unique names for all the script we use,
the full path is not so important as the space we spent of the console.

Change-Id: Ie6fe2ce1ca409033189e1c033a4aebf9e037eaba

templates/scripts/includes/deployment.sh

@@ -232,7 +232,7 @@ die() {
 enable_trace() {
   if "${DEBUG_MODE}" ; then
     set -x
-    export PS4='+\t (${BASH_SOURCE}:${LINENO}): ${FUNCNAME[0]:+${FUNCNAME[0]}(): } '
+    export PS4='+\t (${BASH_SOURCE##*/}:${LINENO}): ${FUNCNAME[0]:+${FUNCNAME[0]}(): } '
   fi
 }