build: Make the Windows Guest Test always pass on PR builds

When running with the merge queue the tests will be fully executed.

Signed-off-by: Rob Bradford <rbradford@rivosinc.com>

.github/workflows/integration-windows.yaml

@@ -1,16 +1,18 @@
 name: Cloud Hypervisor Tests (Windows Guest)
-on: [merge_group]
+on: [merge_group, pull_request]
 
 jobs:
   build:
     name: Tests (Windows Guest)
-    runs-on: garm-jammy
+    runs-on: ${{ github.event_name == 'pull_request' && 'ubuntu-latest' || 'garm-jammy' }}
     steps:
       - name: Code checkout
+        if: ${{ github.event_name != 'pull_request' }}
         uses: actions/checkout@v4
         with:
           fetch-depth: 0
       - name: Install Docker
+        if: ${{ github.event_name != 'pull_request' }}
         run: |
           sudo apt-get update
           sudo apt-get -y install ca-certificates curl gnupg
@@ -20,6 +22,7 @@ jobs:
           sudo apt-get update
           sudo apt install -y docker-ce docker-ce-cli
       - name: Install Azure CLI
+        if: ${{ github.event_name != 'pull_request' }}
         run: |
           sudo apt install -y ca-certificates curl apt-transport-https lsb-release gnupg
           curl -sL https://packages.microsoft.com/keys/microsoft.asc | gpg --dearmor | sudo tee /etc/apt/trusted.gpg.d/microsoft.gpg > /dev/null
@@ -27,12 +30,18 @@ jobs:
           sudo apt update
           sudo apt install -y azure-cli
       - name: Download Windows image
+        if: ${{ github.event_name != 'pull_request' }}
         run: |
           mkdir $HOME/workloads
           az storage blob download --container-name private-images --file "$HOME/workloads/windows-server-2022-amd64-2.raw" --name windows-server-2022-amd64-2.raw --connection-string "${{ secrets.CH_PRIVATE_IMAGES }}"
       - name: Run Windows guest integration tests
+        if: ${{ github.event_name != 'pull_request' }}
         timeout-minutes: 15
         run: scripts/dev_cli.sh tests --integration-windows
       - name: Run Windows guest integration tests for musl
+        if: ${{ github.event_name != 'pull_request' }}
         timeout-minutes: 15
         run: scripts/dev_cli.sh tests --integration-windows --libc musl
+      - name: Skipping build for PR
+        if: ${{ github.event_name == 'pull_request' }}
+        run: echo "Skipping build for PR"