docs: private List<String> extractPortValues(List<String> config, ValueProvider valueProvider) {
          List<String> ret = new ArrayList<>();
          List<String> ports = valueProvider.getList(PORTS, config);
          if (ports == null) {
              return null;
          }
          List<String[]> parsedPorts = EnvUtil.splitOnLastColon(ports);
          for (String[] port : parsedPorts) {
              ret.add(port[1]);
          }
          return ret;
      }