[ci] Automate the verification about signed commit in PRs. (#11714)

.github/workflows/check-verified-commit.yml

@@ -0,0 +1,19 @@
+name: Check signed commits in PR 
+on: [pull_request,pull_request_target]
+jobs:
+  check-signed-commits:
+    name: Check signed commits in PR
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      pull-requests: write
+    steps:
+    - name: Information about how to sign commits see https://docs.github.com/en/authentication/managing-commit-signature-verification/signing-commits
+      # "with comment" below does not work for forks.
+      run: |
+        echo "If you need to sign commits, Please see https://docs.github.com/en/authentication/managing-commit-signature-verification/signing-commits"
+    - name: Check signed commits in PR on fail see above information.
+      uses: 1Password/check-signed-commits-action@v1
+      with:
+        comment: |
+          Thank you for your contribution, but we need you to sign your commits. Please see https://docs.github.com/en/authentication/managing-commit-signature-verification/signing-commits

CONTRIBUTING.md

@@ -54,6 +54,8 @@ For general suggestions or questions about the project or the documentation, you
   * worker
   * doc
 
+* All commit must be signed, if you need to configure your git environement please see [Github documentation on signed commit][https://docs.github.com/en/authentication/managing-commit-signature-verification/signing-commits]
+
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