CI: use a dedicated disk for releases (#12692)

This should make 'no space left on device' problems easier to handle

Use /tmp/releases as local_release_dir CI created machine, while keeping
the same folder on the runner (needed for gitlab-ci runner pods)

tests/cloud_playbooks/roles/packet-ci/vars/main.yml

@@ -44,6 +44,12 @@ cloudinit_config: |
       lock_passwd: False
       ssh_authorized_keys:
         - {{ ssh_key.public_key }}
+  fs_setup:
+    - device: '/dev/disk/by-id/virtio-2825A83CBDC8A32D5E'
+      filesystem: 'ext4'
+      partition: 'none'
+  mounts:
+    - ['/dev/disk/by-id/virtio-2825A83CBDC8A32D5E', '/tmp/releases']
 
 ignition_config:
   ignition:
@@ -56,3 +62,9 @@ ignition_config:
           - wheel
         sshAuthorizedKeys:
           - "{{ ssh_key.public_key }}"
+  storage:
+    filesystems:
+      - device: '/dev/disk/by-id/virtio-2825A83CBDC8A32D5E'
+        format: ext4
+        path: /tmp/releases
+        wipeFilesystem: true