Documenting some useful pages in the Buildkite web UI

[DilumAluthge]

Documenting them here so that they aren't lost to the Slack memory hole.

• Agents: https://buildkite.com/organizations/julialang/agents
• Concurrency groups: https://buildkite.com/organizations/julialang/concurrency-groups
• Builds: https://buildkite.com/organizations/julialang/builds
• Jobs: https://buildkite.com/organizations/julialang/jobs

[DilumAluthge]

Here's my hacky approach to clearing out all of the queues. This is useful when there is a big backlog.

1. Go to https://buildkite.com/organizations/julialang/builds and click on the "Scheduled" button in the right-hand side. Then click on each of the builds that show up, and cancel them.
2. Go to https://buildkite.com/organizations/julialang/builds and click on the "Running" button in the right-hand side. Then click on each of the builds that show up, and cancel them.
3. Go to https://buildkite.com/organizations/julialang/jobs and search for state:scheduled. Then click on each of the jobs that show up, and cancel them.
4. Go to https://buildkite.com/organizations/julialang/jobs and search for state:running. Then click on each of the jobs that show up, and cancel them.