create gihub action for scheduled submodule update

.github/workflows/submodules.yml

@@ -0,0 +1,32 @@
+name: Update submodule vyos-1x
+on:
+  workflow_dispatch:
+  schedule:
+  # 06:00 UTC on Monday
+    - cron:  '0 6 * * 1'
+jobs:
+  updatVyOS-1x:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          repository: rebortg/vyos-documentation
+      - name: update submodule
+        run: |
+          git submodule status
+          git submodule update --init --force
+          cd docs/_include/vyos-1x
+          git checkout current
+          git pull
+          git submodule status
+      - name: Create Pull Request
+        uses: peter-evans/create-pull-request@v3
+        with:
+          token: ${{secrets.GITHUB_TOKEN}}
+          commit-message: Update vyos-1x submodule
+          committer: GitHub <noreply@github.com>
+          author: ${{ github.actor }} <${{ github.actor }}@users.noreply.github.com>
+          title: Update vyos-1x submodule
+          body: |
+            Autoupdate vyos-1x submodule
+          branch: update-dependencies