redfishpower: reduce polling interval in test mode

Problem: When in test mode, the status polling interval is still
set to 1 second.  This can slow down tests.

Reduce the status polling interval to 1 millisecond when in test mode.

src/redfishpower/redfishpower.c

@@ -1161,6 +1161,11 @@ int main(int argc, char *argv[])
  free(hostname);
  }
  hostlist_iterator_destroy(itr);
+
+ /* under test mode we can make the polling interval a lot smaller
+ * lets put it to a millisecond.
+ */
+ status_polling_interval = 1000;
  }
 
  shell(mh);