inline fun <reified T> DocumentSnapshot.toObject(): T?
Returns the contents of the document converted to a POJO or null if the document doesn't exist.
T - The type of the object to create.
Return
The contents of the document in an object of type T or null if the document doesn't
exist.
inline fun <reified T> DocumentSnapshot.toObject(serverTimestampBehavior: ServerTimestampBehavior): T?
Returns the contents of the document converted to a POJO or null if the document doesn't exist.
T - The type of the object to create.
serverTimestampBehavior - Configures the behavior for server timestamps that have not yet
been set to their final value.
Return
The contents of the document in an object of type T or null if the document doesn't
exist.