fix: make tpu_v5e_4 non-preemptible in test config

The executor heuristic auto-tags small CLI jobs as non-preemptible.
With all test workers preemptible, these jobs stayed PENDING forever.
Make the always-on tpu_v5e_4 group non-preemptible so executor-style
jobs can schedule. Also revert the --cpu 2 workaround back to --cpu 1.

Author: rjpower

lib/iris/examples/test.yaml

@@ -33,7 +33,7 @@ controller:
     port: 10000
 
 scale_groups:
-  # Active scale group with capacity
+  # Active scale group with capacity (non-preemptible so executor-style jobs land here)
   tpu_v5e_4:
     num_vms: 1
     resources:
@@ -43,7 +43,7 @@ scale_groups:
       device_type: tpu
       device_variant: v5litepod-4
       device_count: 4
-      preemptible: true
+      preemptible: false
     min_slices: 2
     max_slices: 10
     slice_template:

tests/integration/iris/test_cli_dispatch.py

@@ -55,8 +55,6 @@ def _wait_for_job_state(
 
 def test_cli_submit_and_succeed(integration_cluster):
     """Submit a simple command via 'iris job run' CLI and verify it succeeds."""
-    # Use --cpu 2 to avoid the executor heuristic (≤1 CPU → non-preemptible),
-    # since test cluster workers are all preemptible.
     result = _run_iris_cli(
         integration_cluster.url,
         "job",
@@ -65,7 +63,7 @@ def test_cli_submit_and_succeed(integration_cluster):
         "--job-name",
         "itest-cli-ok",
         "--cpu",
-        "2",
+        "1",
         "--memory",
         "1g",
         "--",
@@ -91,7 +89,7 @@ def test_cli_submit_failing_command(integration_cluster):
         "--job-name",
         "itest-cli-fail",
         "--cpu",
-        "2",
+        "1",
         "--memory",
         "1g",
         "--",