Add GDK workflow

Author: flibitijibibo

.github/workflows/gdk.yml

@@ -0,0 +1,30 @@
+name: Build (GDK)
+
+on: [push, pull_request]
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.run_id }}
+  cancel-in-progress: true
+
+jobs:
+  Build:
+    name: ${{ matrix.platform.name }}
+    runs-on: windows-latest
+
+    strategy:
+      fail-fast: false
+      matrix:
+        platform:
+        - { name: Windows GDK }
+
+    steps:
+      - uses: actions/checkout@v3
+      - name: Download GDK
+        shell: pwsh
+        run: |
+          cd VisualC-GDK
+          dotnet add package Microsoft.GDK.PC.240600 --version 10.0.25398.4271
+      - name: Add msbuild to PATH
+        uses: microsoft/[email protected]
+      - name: Build
+        run: msbuild VisualC-GDK/SDL.sln /m /p:BuildInParallel=true /p:Configuration=Release /p:Platform=Gaming.Desktop.x64