Bors-NG’s merge commits usually have the same name as the GitHub App (bors[bot]@users.noreply.github.com, in the case of the publicly hosted instance at app.bors.tech), but you can actually change the bot’s committer name to whatever you want, even on the hosted instance!
To do it, add something like this to your bors.toml file:
[committer]
name = "notriddle"
email = "[email protected]"
The email should probably be connected to a GitHub account that you control, or it should use the fake keep your email address private one like in the example. The name can be practically anything you like, but if the email is connected to a GitHub account, then GitHub is going to show that account’s username instead of the committer name, so to avoid confusion I recommend making the username and the committer name the same.