Integrate Harbormaster with Buildkite
Summary: Ref T12173. This might need some additional work but the basics seem like they're in good shape.
Test Plan:
- Buildkite is "bring your own hardware", so you need to launch a host to test anything.
- Launched a host in AWS.
- Configured Buildkite to use that host to run builds.
- Added a Buildkite build step to a new Harbormaster build plan.
- Used bin/harbormaster build ... to run the plan.
- Saw buildkite execute builds and report status back to Harbormaster
Reviewers: chad
Reviewed By: chad
Subscribers: PHID-OPKG-gm6ozazyms6q6i22gyam
Maniphest Tasks: T12173
Differential Revision: https://secure.phabricator.com/D17270