Add Danger action to trigger Danger on Buildkite

.github/workflows/run-danger.yml

@@ -0,0 +1,17 @@
+name: ☢️ Trigger Danger On Buildkite
+
+on:
+  pull_request:
+    types: [labeled, unlabeled, ready_for_review]
+
+jobs:
+  dangermattic:
+    if: ${{ (github.event.pull_request.draft == false) }}
+    uses: Automattic/dangermattic/.github/workflows/[email protected]
+    with:
+      org-slug: automattic
+      pipeline-slug: ci-toolkit-buildkite-plugin
+      retry-step-key: danger
+      build-commit-sha: ${{ github.event.pull_request.head.sha }}
+    secrets:
+      buildkite-api-token: ${{ secrets.TRIGGER_BK_BUILD_TOKEN }}