add sync script

.github/workflows/sync.yml

@@ -0,0 +1,24 @@
+name: sync
+
+on:
+  push:
+    branches:
+      - 'main'
+  schedule:
+    - cron: '0 10 * * 1'
+
+jobs:
+  git-sync:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          persist-credentials: false
+      - name: repo-sync
+        uses: repo-sync/github-sync@v2
+        with:
+          source_repo: "https://chromium.googlesource.com/chromium/src/third_party/zlib"
+          source_branch: "main"
+          destination_branch: "zlib"
+          sync_tags: true
+          github_token: ${{ secrets.GITHUB_TOKEN }}

README.md

@@ -1,2 +1,4 @@
 # chromium_zlib
 zlib from chromium
+
+Please check out for 'zlib' branch