prevent all calls to the [Task API](https://developer.hashicorp.com/nomad/api-docs/task-api) from a periodically-dispatched job failing with `403`.

Since no policy for the job id (one with a `periodic-\d+` suffix) matches the generated token claims (that specifically use the [parent job id](https://github.com/hashicorp/nomad/blob/891999789689240006b2a6076b73ddc67249d48d/nomad/structs/structs.go#L10912C19-L10914)).

## steps to reproduce

Create a policy with

```sh
nomad acl policy apply -namespace default -job example example-job <(cat <<EOF
namespace "default" {
  policy = "write"
}
EOF
)
```

Create a job

```hcl
# example.nomad
job "example" {
  datacenters = ["casa"]
  type = "batch"
  priority = 10

  periodic {
    cron             = "*/15 * * * * *"
    prohibit_overlap = true
  }

  group "example" {
    task "example" {
      driver = "docker"

      config {
        image = "curlimages/curl:7.87.0"
        args = [
          "--unix-socket", "${NOMAD_SECRETS_DIR}/api.sock",
          "-H", "Authorization: Bearer ${NOMAD_TOKEN}",
          "--fail-with-body",
          "--verbose",
          "localhost/v1/client/metadata",
        ]
      }


      identity {
        env = true
        file = false
      }
    }
  }

}
```

Run and dispatch
```sh
nomad run example.nomad 
echo "{}" | nomad job dispatch example -
```

It'll fail with a 403, and upon inspecting the claims we find

```json
echo "the second part of the JWT, possibly padded with equal signs" | base64 -d | jq
{
  "nomad_namespace": "default",
  "nomad_job_id": "example",
  "nomad_allocation_id": "dcc6477e-1b20-afbd-b46a-d3810d198b53",
  "nomad_task": "example",
  "nbf": 1682647044,
  "iat": 1682647044
}
```

but current code searches for policies for job id `example/periodic-\d+`