How to use the @stoplight/types.ValidationSeverity.Warn function in @stoplight/types

const result = spectral.run({
      responses: {
        '200': {
          name: 'ok',
        },
        '404': {
          name: 'not found',
        },
      },
    });

    expect(result.results[0]).toEqual({
      name: 'rule1',
      message,
      severity: ValidationSeverity.Warn,
      severityLabel: ValidationSeverityLabel.Warn,
      path: ['responses', '404', 'description'],
    });
  });