TagBot trigger issue

This issue is used to trigger TagBot; feel free to unsubscribe. If you haven't already, you should update your `TagBot.yml` to include issue comment triggers. Please see [this post on Discourse](https://discourse.julialang.org/t/ann-required-updates-to-tagbot-yml/49249) for instructions and more details. If you'd like for me to do this for you, comment `TagBot fix` on this issue. I'll open a PR within a few hours, please be patient!