Feature: add CLA check

Author: bochencwx

.github/workflows/cla.yml

@@ -0,0 +1,34 @@
+name: "CLA Assistant"
+on:
+  issue_comment:
+    types: [created]
+  pull_request_target:
+    types: [opened, synchronize, reopened]
+
+# explicitly configure permissions, in case your GITHUB_TOKEN workflow permissions are set to read-only in repository settings
+permissions:
+  actions: write
+  contents: write
+  pull-requests: write
+  statuses: write
+
+jobs:
+  CLAAssistant:
+    runs-on:
+      group: Default
+      labels: trpc-cpp-plugins-ci
+    steps:
+      - name: "CLA Assistant"
+        if: (github.event.comment.body == 'recheck' || github.event.comment.body == 'I have read the CLA Document and I hereby sign the CLA') || github.event_name == 'pull_request_target'
+        uses: contributor-assistant/[email protected]
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          PERSONAL_ACCESS_TOKEN: ${{ secrets.CLA_DATABASE_ACCESS_TOKEN }}
+        with:
+          remote-organization-name: trpc-group
+          remote-repository-name: cla-database
+          path-to-signatures: 'signatures/${{ github.event.repository.name }}-${{ github.repository_id }}/cla.json'
+          path-to-document: 'https://github.com/trpc-group/cla-database/blob/main/Tencent-Contributor-License-Agreement.md'
+          # branch should not be protected
+          branch: 'main'
+          allowlist: bot*