Add homu repository under automation

[Kobzol]

Repo: https://github.com/rust-lang/homu

I guess that not requiring reviews is to make it easier to do emergency fixes when bors breaks?

Original configuration from GH:

org = "rust-lang"
name = "homu"
description = "A bot that integrates with GitHub and your favorite continuous integration service"
bots = []

[access.teams]
infra = "write"
security = "pull"

[access.individuals]
shepmaster = "write"
rylev = "admin"
pietroalbini = "admin"
kennytm = "write"
badboy = "admin"
jdno = "admin"
Kobzol = "write"
Mark-Simulacrum = "admin"
rust-lang-owner = "admin"

[[branch-protections]]
pattern = "master"
ci-checks = []
dismiss-stale-review = false
pr-required = true
review-required = false

[rylev]

I see that this reflects the status quo so not a blocker, but it does seem surprising to me.