This allows passing in custom triggers to trigger a (re)deploy.
For example, a caller can put an AWS instance ID into the triggers to
cause a redeploy whenever the instance ID has changed.
The `target_name` terraform variable was doing something similar, but
`triggers` is more generic, allowing multiple triggers, without having
to stringify them.
We also don't need to trigger on the attrpath - it can be changed, and
as long as it still evaluates to the same
`data.external.nixos_system.result.drv` (which is checked on every
plan), no redeploy needs to be made.
Change-Id: I94ce787a50830b87b6f53c08e042e4abe4036bdd
Reviewed-on: https://cl.tvl.fyi/c/depot/+/8191
Tested-by: BuildkiteCI
Reviewed-by: tazjin <tazjin@tvl.su>
Autosubmit: flokli <flokli@flokli.de>