forgejo-ci: add test build workflow

.forgejo/workflows/test-build.yaml

@@ -0,0 +1,40 @@
+on: 
+  pull_request:
+    types: [ assigned, opened, synchronize, reopened ]
+
+jobs:
+  build-test:
+    runs-on: x86_64
+    container:
+      image: alpine:3.20
+    env:
+      CI_PROJECT_DIR: ${{ github.workspace }}
+      CI_DEBUG_BUILD: ${{ runner.debug }}
+      CI_MERGE_REQUEST_PROJECT_URL: ${{ github.server_url }}/${{ github.repository }}
+      CI_MERGE_REQUEST_TARGET_BRANCH_NAME: ${{ github.base_ref }}
+    steps:
+      - name: Environment setup
+        run: |
+          doas apk add rpm wget losetup coreutils eudev e2fsprogs xen
+          cd /etc/apk/keys
+          doas curl -JO https://ayakael.net/api/packages/forge/alpine/key
+      - name: Repo pull
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 500
+      - name: RPM build
+        run: |
+          git clone https://github.com/QubesOS/qubes-builder
+          mkdir qubes-builder/qubes-src
+          ln -s $CI_PROJECT_DIR qubes-builder/qubes-src/builder-alpine
+          cp builder.conf qubes-builder/.
+          git clone https://github.com/QubesOS/qubes-linux-template-builder qubes-builder/qubes-src/linux-template-builder
+          echo "%define _arch x86_64" >> qubes-builder/qubes-src/linux-template-builder/templates.spec
+          cd qubes-builder
+          make linux-template-builder
+          cp qubes-src/linux-template-builder/rpm/noarch/qubes-template-*.rpm $GITHUB_WORKSPACE/.
+      - name: Package upload
+        uses: forgejo/upload-artifact@v3
+        with:
+          name: package
+          path: packages