Update github action

.github/workflows/build.yml

@@ -6,6 +6,56 @@ on:
       - v*
 
 jobs:
+
+  flatpak:
+    name: Flatpak Build
+    runs-on: ubuntu-latest
+    needs: [cachedeps]
+
+    container:
+      image: bilelmoussaoui/flatpak-github-actions:gnome-45
+      options: --privileged
+
+    steps:
+      - name: Checkout Git repository
+        uses: actions/checkout@v4
+        with:
+          submodules: recursive
+
+      - uses: actions/download-artifact@master
+        with:
+          name: flatpak-sources
+          path: flatpak/
+
+      - name: Install Node.js, NPM and Yarn
+        uses: actions/[email protected]
+        with:
+          node-version: 18
+
+      - name: Set up flatpak build cache
+        uses: actions/cache@v4
+        continue-on-error: false
+        with:
+          path: |
+            build/
+            .flatpak-builder/
+            flatpak-node/
+          key: ${{ runner.os }}-${{ runner.arch }}-flatpak-builder-${{ hashFiles('flatpak/*') }}
+          restore-keys: ${{ runner.os }}-${{ runner.arch }}-flatpak-builder-
+
+      - uses: flatpak/flatpak-github-actions/flatpak-builder@v6
+        with:
+          bundle: XStreaming.flatpak
+          manifest-path: flatpak/io.github.Geocld.XStreaming.yml
+          cache-key: flatpak-builder-${{ github.sha }}
+
+      - name: Release flatpak
+        uses: softprops/action-gh-release@v2
+        if: startsWith(github.ref, 'refs/tags/v')
+        with:
+          files: XStreaming.flatpak
+          draft: true
+
   release:
     name: Build/release Electron app
     runs-on: ${{ matrix.os }}