The meeting scheduler should include the GitHub id of the meeting requester in the GitHub issue

When the meeting scheduler creates an issue for a REST API review, it includes the name of the person requesting the review, e.g.:
```
Review Created By: Nicolas Rafalowski
```

But if I want to tag this person in the issue, e.g. to ask them to link a PR to the issue, I need to find their GitHub id. Rather than looking this up manually, it would be nice if the meeting scheduler could do that lookup and just include it in the initial issue description:
```
Review Created By: Nicolas Rafalowski @nrafalowski
```

Start by locating the meeting scheduler entry point that creates GitHub issues for REST API reviews and find where the “Review Created By” line is assembled. Check how the requester’s GitHub identity is available, then verify that generated issue descriptions include both the display name and @handle.

Written by the indexing model from the issue text.