[CI] Use bigger partition as work dir for metal3 job

In Rackspace env a bigger partition is available and configured
as /dev/xvde1 but not mounted.
We should use that as working dir for the metal3 job as the
standard one is too small and the job fails regularly when
running there.

This allows to make the metal3 job voting again.

Change-Id: I4d50b9c07367a5b1ad25887d87cf2e29ac6b4257

playbooks/metal3-ci/run.yaml

@@ -21,6 +21,24 @@
           TEST_MAX_TIME: 200
           WORKER_MACHINE_COUNT: 1
 
+    - name: Format bigger partition for /opt/metal3-dev-env if available
+      filesystem:
+        fstype: ext4
+        dev: /dev/xvde1
+        force: true
+      become: true
+      when: ansible_devices.xvde.partitions.xvde1 is defined
+
+    - name: Mount /opt/metal3-dev-env in bigger partition if available
+      mount:
+        path: /opt/metal3-dev-env
+        src: /dev/xvde1
+        fstype: ext4
+        state: ephemeral
+        boot: false
+      become: true
+      when: ansible_devices.xvde.partitions.xvde1 is defined
+
     # TODO(dtantsur): add metal3-io/metal3-dev-env as a recognized project to
     # https://opendev.org/openstack/project-config/src/commit/e15b9cae77bdc243322cee64b3688a2a43dd193c/zuul/main.yaml#L1416
     - name: Clone metal3-dev-env

zuul.d/project.yaml

@@ -52,8 +52,7 @@
         # NOTE(TheJulia): At present, metal3 doesn't leverage
         # stable branches, and as far as we are aware these jobs
         # can be removed once this branch is made stable.
-        - metal3-integration:
-            voting: false
+        - metal3-integration
         # Non-voting jobs
         - ironic-inspector-tempest:
             voting: false
@@ -96,7 +95,7 @@
         # NOTE(TheJulia): At present, metal3 doesn't leverage
         # stable branches, and as far as we are aware these jobs
         # can be removed once this branch is made stable.
-        #- metal3-integration
+        - metal3-integration
     experimental:
       jobs:
         # NOTE(dtantsur): this job is rarely used, no need to run it always.