Add CLA Bot as workflow

.github/workflows/cla.yml

@@ -0,0 +1,22 @@
+name: "CLA-Bot"
+on:
+  issue_comment:
+    types: [created]
+  pull_request_target:
+    types: [ opened, closed, synchronize ]
+
+jobs:
+  CLAssistant:
+    runs-on: ubuntu-latest
+    steps:
+      - name: "CLA-Bot signature check"
+        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: cla-assistant/github-action@v2.1.3-beta
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          PERSONAL_ACCESS_TOKEN : ${{ secrets.CLA_BOT_ACCESS_TOKEN }}
+        with:
+          remote-repository-name: Home
+          path-to-signatures: '.github/signatures/cla.json'
+          path-to-document: 'https://github.com/wixtoolset/Home/blob/master/DNFCLA.md'
+          allowlist: wixbot