updated backend author service, to handle the fact that SQLAlchemy rows arent tuples

backend/services/author_service.py

@@ -62,10 +62,7 @@ async def list_authors(
     result = await db.execute(base)
     authors = []
     for row in result.all():
-        if isinstance(row, tuple):
         author = row[0]
-        else:
-            author = row
         data = {c.name: getattr(author, c.name) for c in author.__table__.columns}
         authors.append(data)