add Slack workflow

.github/workflows/ci.yml

@@ -35,3 +35,8 @@ jobs:
           python-version: '3.12'
       - name: file_sync test
         run: python ./private/test/file_sync_test.py
+  slack_test_fail:
+    runs-on: ubuntu-latest
+    steps:
+      - name: fail step
+        run: exit 1

.github/workflows/slack.yml

@@ -0,0 +1,31 @@
+# SPDX-License-Identifier: MIT-0
+
+---
+name: slack
+on:
+  workflow_run:
+    workflows: [ci]
+    types: [completed]
+  # TODO: testing steps to initially register the workflow on GHA, REMOVE
+  push:
+  pull_request:
+
+jobs:
+  notify:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Notify Build Cop Slack
+        uses: ravsamhq/notify-slack-action@v2
+        with:
+          notify_when: "failure"
+          status: ${{ github.event.workflow_run.conclusion }}
+          notification_title: >
+            ${{github.event.workflow_run.name}} -
+            ${{github.event.workflow_run.conclusion}} on ${{github.event.workflow_run.head_branch}} -
+            <${{github.server_url}}/${{github.repository}}/actions/runs/${{github.event.workflow_run.id}}|View Failure>
+          message_format: >
+            :fire: *${{github.event.workflow_run.name}}*
+            ${{github.event.workflow_run.conclusion}} in
+            <${{github.server_url}}/${{github.repository}}/tree/${{github.event.workflow_run.head_branch}}|${{github.repository}}>
+        env:
+          SLACK_WEBHOOK_URL: ${{ secrets.SLACK_BUILDCOP_URL }}