ci: Fix low-scale CI.

The low-scale CI scenario needed updating.

* It tried to use "localhost" as the host, which is no longer possible.
  The orchestrator and the ovn-tester container both need to be able to
  access the same hosts using the physical deployment file.
* It was missing a tester section.

.cirrus.yml

@@ -5,10 +5,11 @@ low_scale_task:
     image: family/fedora-cloud-35
     platform: linux
     memory: 8G
+    use_static_ip: true
 
   env:
     DEPENDENCIES: git ansible podman podman-docker
-    PHYS_DEPLOYMENT: ${CIRRUS_WORKING_DIR}/physical-deployments/localhost.yml
+    PHYS_DEPLOYMENT: ${CIRRUS_WORKING_DIR}/physical-deployments/ci.yml
 
   runtime_cache:
     folder: runtime-cache
@@ -30,6 +31,9 @@ low_scale_task:
     - tar -xzf runtime-cache/runtime.tar.gz || true
 
   install_script:
+    - 'sed -i
+        "s/<ip>/$(ip route get 8.8.8.8 | head -1 | sed 's/.*src \([0-9\.]*\).*/\1/'/g)"
+        ${PHYS_DEPLOYMENT}'
     - ./do.sh install
 
   pack_caches_script:

physical-deployments/ci.yml

@@ -0,0 +1,12 @@
+registry-node: <ip>
+internal-iface: eno1
+
+central-node:
+  name: <ip>
+
+tester-node:
+  name: <ip>
+  ssh_key: /root/.ssh/id_rsa
+
+worker-nodes:
+  - <ip>