(gha) Test install in gha on other os's using containers

Github actions only provides a few ubuntu vms. This patch takes a stab
at adding a matrix of base os containers to run on ubuntu 24.04 in an
attempt to simulate install on those variants.

To simplify the workflow, I'm not attempting to install bolt as a runner
for these additional cases. Instead, the facts module is checked out and
I simulate the run environment by supplying the Bolt PT__installdir var
to the task script executed directly.

Author: jpartlow

.github/workflows/pr_testing.yaml

@@ -20,8 +20,11 @@ jobs:
         run: shellcheck tasks/*.sh
 
   test-install-task-on-ubuntu:
+    strategy:
+      matrix:
+        os: [ubuntu-20.04, ubuntu-22.04]
     # Perforce hasn't yet released bolt on 24.04.
-    runs-on: ubuntu-22.04
+    runs-on: ${{ matrix.os }}
     needs: shellcheck
     steps:
       - uses: actions/checkout@v4
@@ -38,3 +41,29 @@ jobs:
       - name: Verify openvox-agent is installed
         run: |-
           [[ "$(/opt/puppetlabs/bin/puppet --version)" =~ [0-9]+\.[0-9]+\.[0-9]+ ]]
+
+  test-install-task-on-other-os-via-containers:
+    strategy:
+      matrix:
+        image:
+          - rockylinux/rockylinux:7
+          - rockylinux/rockylinux:8
+          - rockylinux/rockylinux:9
+          - rockylinux/rockylinux:10
+          - debian/debian:10
+          - debian/debian:11
+          - debian/debian:12
+          - sles/sles:15
+    needs: shellcheck
+    container: ${{ matrix.image }}
+    steps:
+      - uses: actions/checkout@v4
+      - name: Checkout facts module
+        run: git clone https://github.com/puppetlabs/puppetlabs-facts.git ../facts
+      - name: Run openvox-agent install task manually
+        env:
+          PT__installdir: "${PWD}/.."
+        run: sudo -E tasks/install_linux.sh
+      - name: Verify openvox-agent is installed
+        run: |-
+          [[ "$(/opt/puppetlabs/bin/puppet --version)" =~ [0-9]+\.[0-9]+\.[0-9]+ ]]