Add sync upstream workflow

Change-Id: I36a0f51e0e5cf19db0fcad901ff84d8117d71e23

Author: ArchieMeng

.github/workflows/sync-upstream.yml

@@ -0,0 +1,31 @@
+name: Sync/Rebase on Upstream
+on:
+  schedule:
+  - cron: "0 0 * * *"  # run daily
+  workflow_dispatch:   # run manually
+
+permissions:
+  contents: write
+
+jobs:
+  sync:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@master
+      with:
+        fetch-depth: 0  # Fetch all history for rebase
+    - name: Get initial hash
+      id: get-initial-hash
+      run: echo "init_hash=$(git rev-parse HEAD)" >> $GITHUB_OUTPUT
+    - uses: archiemeng/rebase-upstream-action@master
+      with:
+        branch: ${{ github.ref_name }}
+        depth: 0
+    - name: Get current hash
+      id: get-current-hash
+      run: echo "cur_hash=$(git rev-parse HEAD)" >> $GITHUB_OUTPUT
+    - name: Workflow Dispatch
+      uses: benc-uk/workflow-dispatch@v1.2.4
+      if: ${{ steps.get-initial-hash.outputs.init_hash != steps.get-current-hash.outputs.cur_hash && hashFiles('.github/workflows/build.yml') != '' }}
+      with:
+        workflow: build.yml