dbGetDocument<T> function
Implementation
Future<String?> dbGetDocument<T>(String tableName, String doc, {
String? field1, String? isEqualTo1
}) async{
// T t;
// QuerySnapshot<Map<String, dynamic>> querySnapshot;
// if (field1 != null && isEqualTo1 != null)
// querySnapshot = await FirebaseFirestore.instance.collection(tableName).where(field1, isEqualTo: isEqualTo1).get();
// else
// querySnapshot = await FirebaseFirestore.instance.collection(tableName).get();
return null;
}