github: check that we can use nested virt inside GHA VMs

Signed-off-by: Simon Deziel <simon.deziel@canonical.com>

.github/workflows/tests.yml

@@ -154,6 +154,17 @@ jobs:
           sudo snap install lxd --channel 5.21/stable || sudo snap refresh lxd --channel 5.21/stable
           sudo lxd init --auto
 
+          # Test if we can nest a VM inside a VM on a GHA VM
+          sudo lxc launch ubuntu-minimal:22.04 v1 --vm -c limits.memory=2GiB
+          sleep 300
+          sudo lxc exec v1 -- lxd init --auto
+          sudo lxc exec v1 -- lxc launch ubuntu-minimal-daily:22.04 n1 --vm -c limits.memory=512MiB
+          sleep 600
+          sudo lxc exec v1 -- lxc list
+          sudo lxc exec v1 -- lxc exec n1 -- cloud-init status --long
+
+          sudo lxc delete -f v1
+
           chmod +x ~
           cd microcloud/test
           sudo --preserve-env=GITHUB_ACTIONS,TEST_STORAGE_SOURCE,DEBUG DEBUG=1 ./main.sh