How do you query by a content relationship in a group, but in graphql?

[jason (Jason Farrell)]

In the REST API, you can filter data by a value in a content relationship in a group, but I can't seem to find how to do so in graphql.

For example, the documentation in REST:

Rest API Technical Reference

But in graphql, the documentation doesn't mention groups:

Fetch Data with GraphQL

I need to be able to filter by service, and I'm not seeing it as an option here:

Please help!