title: Can we delete an attribute of a document in firestore automatically?
body: <p>I am working on an android project using java where we have a subscription for pro users. Right now I am using firestore as my database, is there any way that I can automatically change the pro attribute in user from true to false in a specific time automatically as the subscription time end? In my user collection's document, there are attributes is_a_pro and pro_availability_time which is in json (YYYY-MM-DD). Thank you</p>