Provide an interface to job level settings

There are some settings that are impossible to set with this action. In particular we have a private AWS ECR docker registry that we log in to using the recommended OIDC method so that we can generate a short-lived CI specific token.

Part of this process requires setting the permissions: id-token: write setting on the job, or the GH token will not have enough permission to accomplish its task. This leaves us in a situation where we either have to abandon the use of this plugin, or abandon the use of OIDC. As an ops professional, I would lean toward the former, but some of our developers would probably prefer to keep using this plugin, so I would just like to request that you offer some sort of interface to this.

If you want to scope it just to permissions that's fine, but I'd prefer something a bit more generic to set any other settings that a job might want, that are currently unsettable by this generator.

The issue names no files, tests, or entry points. Start by tracing how this Scala sbt plugin generates GitHub Actions jobs, then determine where job-level settings and permissions could be represented; done means users can configure the requested OIDC permission or broader job settings and the behavior is covered by tests.