Routes GraphQL query has depth of 8

[joeyAghion]

(Similar to https://github.com/artsy/force/issues/1823.) Upon trying to enforce a depth limit on GraphQL queries, we noticed the Route queries occurring with depth of 9. I'm not sure what the source of these are, but they're visible in logs.

We've expanded the allowed depth to 10, but we should try to flatten this out if possible so we can enforce a more reasonable limit.