added sync fork with upstream yaml

.github/workflows/sync_with_main.yml

@@ -0,0 +1,37 @@
+on:
+  schedule:
+    - cron:  '0 */2 * * *'
+    # scheduled every 2 hours
+  workflow_dispatch:  # click the button on Github repo!
+
+jobs:
+  sync_with_upstream:
+    runs-on: ubuntu-latest
+    name: Sync main with upstream latest
+
+    steps:
+    # Step 1: run a standard checkout action, provided by github
+    - name: Checkout main
+      uses: actions/checkout@v2
+      with:
+        ref: main
+
+    # Step 2: run this sync action - specify the upstream repo, upstream branch to sync with, and target sync branch
+    - name: Pull (Fast-Forward) upstream changes
+      id: sync
+      uses: aormsby/[email protected]
+      with:
+        upstream_repository: apache/tvm
+        upstream_branch: main
+        target_branch: main
+        git_pull_args: --ff-only                    # optional arg use, defaults to simple 'pull'
+        github_token: ${{ secrets.GITHUB_TOKEN }}   # optional, for accessing repos that require authentication
+
+    # Step 3: Display a message if 'sync' step had new commits (simple test)
+    - name: Check for new commits
+      if: steps.sync.outputs.has_new_commits
+      run: echo "There were new commits."
+
+    # Step 4: Print a helpful timestamp for your records (not required, just nice)
+    - name: Timestamp
+      run: date