Число запросов судя по сообщению:
$ composer update it-for-free/rusphp
Loading composer repositories with package information
GitHub API limit (60 calls/hr) is exhausted, could not fetch https://api.github.com/repos/yiisoft/yii.... Create a GitHub OAuth token to go over the API rate limit. You can also wait until 2018-10-26 13:49:05 for the rate limit to reset.