Remove "dead" code

This also removes the code that got commented off in Nandaka#1239, because either it's no longer need (so it doesn't need to be in the code at all) or it may be needed "sometimes" in which case it should probably live uncommented inside an `if` block.

PixivUtil2.py

@@ -1724,15 +1724,7 @@ def main():
               Fore.CYAN + Style.BRIGHT + "https://github.com/Nandaka/PixivUtil2?tab=readme-ov-file#a-usage" + Style.RESET_ALL)
 
         username = __config__.username
-        # if username == '':
-        #     username = input('Username ? ').rstrip("\r")
-        # else:
-        #     msg = f'Using Username: {username}'
-        #     PixivHelper.print_and_log('info', msg)
-
         password = __config__.password
-        # if password == '':
-        #     password = getpass.getpass('Password ? ')
 
         if np_is_valid and options.number_of_pages != 0:  # Yavos: overwrite config-data
             PixivHelper.print_and_log("info", f'Limit up to: {options.number_of_pages} page(s). (set via commandline)')