docs: private String urlEncodeFilters(final Map<String, List<String>> filters) throws DockerException {
      try {
        final String unencodedFilters = objectMapper().writeValueAsString(filters);
        if (!unencodedFilters.isEmpty()) {
          return urlEncode(unencodedFilters);
        }
      } catch (IOException e) {
        throw new DockerException(e);
      }
      return null;
    }