[ticket/12352] Remove usages of user_pass_convert column

PHPBB3-12352

phpBB/includes/ucp/ucp_activate.php

@@ -78,7 +78,6 @@ class ucp_activate
 				'user_actkey'		=> '',
 				'user_password'		=> $user_row['user_newpasswd'],
 				'user_newpasswd'	=> '',
-				'user_pass_convert'	=> 0,
 				'user_login_attempts'	=> 0,
 			);