node-core-utils doesn't understand rate-limits

[avivkeller]

When a rate limit is encountered, the utility currently logs the following message:

✖ Failed to retrieve user info.
username must be a string, received undefined

This could be confusing for collaborators. Ideally, the log should indicate that a rate limit has been reached, such as "Rate limit reached, please try again later." For reference, the GitHub API includes an x-ratelimit-reset header with the specific reset time.