About the group feature

[m-narita-s-style]

Hello

Thank you for creating such a great tool.
I want to use this tool.

I've been running the tutorial for a while and noticed that the group feature doesn't work.

https://square.github.io/finch/intro/concepts/#client-and-execution-groups

In fact, there does not appear to be a group attribute.

https://github.com/square/finch/blob/e72f5b0b346c035c12002dea629e79c50a29d9a1/config/file.go#L314-L329

Has this feature been implemented yet?