sync with upstream

.github/workflows/sync_upstream.yml

@@ -0,0 +1,47 @@
+name: 'Sync With Upstream'
+
+on:
+  schedule:
+    - cron:  '30 0 * * *'
+      tags-ignore:
+        - '**'
+  workflow_dispatch:
+
+jobs:
+  sync_latest_from_upstream:
+    runs-on: ubuntu-latest
+    name: Sync latest commits from upstream repo
+    if: ${{ !startsWith(github.ref, 'refs/tags/') }}
+    steps:
+      - uses: tgymnich/[email protected]
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+          base: 202405-broadcom
+          head: 202405
+          merge_method: rebase
+
+# Now we need to update the hashes used for sonic-swss and sonic-sairedis
+      - name: Checkout sonic-build
+        uses: actions/checkout@v4
+        with:
+          submodules: "recursive"
+          fetch-depth: 0
+      - name: Update hashes
+        run: |
+          git config --global user.name '[github actions]'
+          git config --global user.email '[email protected]'
+          git pull
+          cd src/sonic-swss
+          git checkout 202405-broadcom
+          git pull
+          cd ../sonic-sairedis
+          git checkout 202405-broadcom
+          git pull
+          cd ../..
+          git add .
+          if git status | grep "nothing to commit" > /dev/null ; then
+            echo "nothing to commit"
+          else
+            git commit -am "update sonic-swss and sonic-sairedis branches"
+            git push
+          fi