User-data script to bootstrap self-hosted runner on ASG (#4)

This runner-supervisor script has been manually uploaded to S3 (it was too big
to include in the userdata)

The cloud init script has been manually uploaded by running, and the ASG
is configured to pick the Latest version already, so new instances will
start using the new script.

```
aws --profile airflow ec2 create-launch-template-version \
    --launch-template-name GithubRunner \
    --launch-template-data UserData="$(base64 -w0 cloud-init.yml)" \
    --source-version='$Latest'
```
3 files changed