New CLA workflow: Uses a github action in

trustgraph-ai/contributor-license-agreement

This blocks a PR until the commiter responds with a message
of agreement with the CLA terms.

.github/workflows/cla.yml

@@ -0,0 +1,25 @@
+name: CLA Assistant
+
+on:
+  issue_comment:
+    types: [created]
+  pull_request_target:
+    types: [opened, synchronize, reopened]
+
+permissions:
+  actions: write
+  contents: write
+  pull-requests: write
+  statuses: write
+
+jobs:
+  CLAssistant:
+    runs-on: ubuntu-latest
+    steps:
+      - name: CLA Assistant
+        uses: trustgraph-ai/contributor-license-agreement/action@main
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          PERSONAL_ACCESS_TOKEN: ${{ secrets.CLA_ASSISTANT_PAT }}
+        with:
+          allowlist: 'dependabot,dependabot[bot],github-actions,github-actions[bot]'