gha: Create Mariner host as part of k8s tests

The current testing setup only supports running Kata on top of an Ubuntu
host. This adds Mariner to the matrix of testable hosts for k8s
tests, with Cloud Hypervisor as a VMM.

As preparation for the upcoming PR that will change only the actual test
code (rather than workflow YAMLs), this also introduces a new file
`setup.sh` that will be used to set host-specific parameters at test
run-time.

Fixes: kata-containers/tests#5528

Signed-off-by: Aurélien Bombo <abombo@microsoft.com>

.github/workflows/run-k8s-tests-on-aks.yaml

@@ -17,10 +17,15 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
+        host_os:
+          - ubuntu
         vmm:
           - clh
           - dragonball
           - qemu
+        include:
+          - host_os: cbl-mariner
+            vmm: clh
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
@@ -46,7 +51,8 @@ jobs:
             -n "${{ github.event.pull_request.number }}-${{ github.event.pull_request.head.sha }}-${{ matrix.vmm }}-amd64" \
             -s "Standard_D4s_v5" \
             --node-count 1 \
-            --generate-ssh-keys
+            --generate-ssh-keys \
+            ${{ matrix.host_os == 'cbl-mariner' && '--os-sku mariner --workload-runtime KataMshvVmIsolation' }}
 
       - name: Install `bats`
         run: |
@@ -76,10 +82,11 @@ jobs:
         timeout-minutes: 30
         run: |
           pushd tests/integration/kubernetes
-          sed -i -e 's|runtimeClassName: kata|runtimeClassName: kata-${{ matrix.vmm }}|' runtimeclass_workloads/*.yaml
+          bash setup.sh
           bash run_kubernetes_tests.sh
           popd
         env:
+          KATA_HOST_OS: ${{ matrix.host_os }}
           KATA_HYPERVISOR: ${{ matrix.vmm }}
 
       - name: Delete AKS cluster

tests/integration/kubernetes/run_kubernetes_tests.sh

@@ -62,6 +62,10 @@ if [ ${KATA_HYPERVISOR} == "qemu-snp" ]; then
 	exit 0
 fi
 
+if [ ${KATA_HOST_OS} == "cbl-mariner" ]; then
+	exit 0
+fi
+
 # we may need to skip a few test cases when running on non-x86_64 arch
 arch_config_file="${kubernetes_dir}/filter_out_per_arch/${TARGET_ARCH}.yaml"
 if [ -f "${arch_config_file}" ]; then

tests/integration/kubernetes/setup.sh

@@ -0,0 +1,14 @@
+#!/usr/bin/env bash
+# Copyright (c) 2023 Microsoft Corporation
+#
+# SPDX-License-Identifier: Apache-2.0
+
+set -o errexit
+set -o nounset
+set -o pipefail
+
+set_runtime_class() {
+    sed -i -e "s|runtimeClassName: kata|runtimeClassName: kata-${KATA_HYPERVISOR}|" runtimeclass_workloads/*.yaml
+}
+
+set_runtime_class