Fix bug with auth.signed_in

If header doesn't exist, name will be None, which is not equal to an empty string making signed_in pass. Changed to bool because None and empty string are both falsey

src/replit/maqpy/app.py

@@ -39,7 +39,7 @@ class ReplitAuthContext:
         Returns:
             bool: whether or not the authentication is activated.
         """
-        return self.name != ""
+        return bool(self.name)
 
 
 class Request(flask.Request):