added descriptor object to Account class

Author: sandeepsuryaprasad

py/selenium/webdriver/common/fedcm/account.py

@@ -32,7 +32,7 @@ def __get__(self, obj, cls) -> Optional[str]:
         return obj._account_data.get(self.name)
 
     def __set__(self, obj, value) -> None:
-        raise AttributeError(f"Cannot set readonly attribute")
+        raise AttributeError("Cannot set readonly attribute")
 
 
 class Account: