message: Add preferred languages and expiration date to security.txt
diff: @@ -183,11 +183,15 @@ app.use((req, res, next) => {
  app.use(metrics.observeRequestMetricsMiddleware())
  /* Security Policy */
  +let securityTxtExpiration = new Date()
  +securityTxtExpiration.setFullYear(securityTxtExpiration.getFullYear() + 1)
  app.get('/.well-known/security.txt', verify.accessControlChallenges())
  app.use('/.well-known/security.txt', securityTxt({
  contact: config.get('application.securityTxt.contact'),
  encryption: config.get('application.securityTxt.encryption'),
  - acknowledgements: config.get('application.securityTxt.acknowledgements')
  + acknowledgements: config.get('application.securityTxt.acknowledgements'),
  + preferredLanguages: [...new Set(locales.map(locale => locale.key.substr(0, 2)))].join(', '),
  + expires: securityTxtExpiration.toUTCString()
  }))
  /* robots.txt */
  