code: @Override
      public <V> V invoke(Callable<V> callable) {
          try {
              return super.invoke(callable);
          } catch (Exception ex) {
              LOGGER.debug("Catched exception, suppressing, returning null", ex);
              return null;
          }
      }
docs: Suppressing exceptions version of the same method from
  {@code ExecutorCommand}. Invokes code synchronously with circuit breaker
  and cache if configured.
  
  @param <V> type of returned value
  @param callable invoked by executor to return value
  @return {@code V} value returned by callable