Added workflow to build next branch

Author: GrabowskiM

.github/workflows/build-on-ds-update.yaml

@@ -1,10 +1,27 @@
-name: Build on DS update
+name: Prepare next branch
 
 on:
   workflow_dispatch:
 
+permissions:
+  contents: write
+
 jobs:
-  build:
+  sync:
     runs-on: ubuntu-latest
     steps:
-      - run: echo "ok"
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Configure git
+        run: |
+          git config user.email "github-actions[bot]@users.noreply.github.com"
+          git config user.name "github-actions[bot]"
+
+      - name: Run prepare_next.sh
+        run: bash bin/prepare_next.sh -v ${{ vars.NEXT_BRANCH_VERSION }} -b ${{ vars.NEXT_BRANCH_SOURCE }}
+
+      - name: Push to next branch
+        run: git push origin HEAD:${{ vars.NEXT_BRANCH_VERSION }}-next