Expand size for test buffer.

This is a partial backport of eclipse-cyclonedds#1947

Signed-off-by: Chris Lalancette <clalancette@gmail.com>

src/core/xtests/rhc_torture/rhc_torture.c

@@ -649,7 +649,7 @@ static void test_conditions (dds_entity_t pp, dds_entity_t tp, const int count,
           if (conds[ci] <= 0) abort ();
           rhcconds[ci] = get_condaddr (conds[ci]);
           if (print) {
-            char buf[18];
+            char buf[19];
             snprintf (buf, sizeof (buf), "conds[%d]", ci);
             print_cond_w_addr (buf, conds[ci]);
           }