Update docker_slack.yml

.github/workflows/docker_slack.yml

@@ -1 +1,25 @@
+name: Publish slack message
+on:
+  push:
+    branches: [ main ]
+    paths:
+      - docker/**
+  workflow_run:
+    workflows: [Build and push final image]
+    types:
+      - completed
+  workflow_dispatch:
+
+jobs:
+  publish-slack:
+    runs-on: self-hosted
+    steps:
+      - run: echo 'The triggering workflow failed'
+      - name: Publish slack message
+        uses: ./.github/action_templates/slack
+        with:
+          slack-webhook-url: ${{ secrets.SLACK_WEBHOOK_URL }}
+          job-status: ${{ job.status }}
+          pull_request_url: ${{ github.event.pull_request.html_url }}
+          head_commit_url: ${{ github.event.head_commit.url }}