echo Drupal::service('date.formatter')->formatInterval($seconds);

namespace Drupalmy_module;

use DrupalCoreDependencyInjectionContainerBuilder;
use DrupalCoreDependencyInjectionServiceProviderBase;

/**
 * Modifies the date formatter service.
 */
class MyModuleServiceProvider extends ServiceProviderBase {

  /**
   * {@inheritdoc}
   */
  public function alter(ContainerBuilder $container) {
    // Overrides date.formatter class for custom interval formatting.
    $definition = $container->getDefinition('date.formatter');
    $definition->setClass(DateFormatter::class);
  }
}