title: Can I add days to a Cloud Firestore server timestamp?
body: <p>I am writing a React Native app that creates a coupon for a user that has a date created field as well as date expires in Firestore. The date expired is the date created plus some days (e.g 7)</p>
  
  <p>Ideally I would like to use firestore.FieldValue.serverTimestamp() in my firebase function for the created plus add 7 days to this for the expiry to avoid having the user generate the date.</p>
  
  <p>Is there a way for this to be done?</p>