Merge pull request #726 from citizensadvice/dependabot/github_actions/citizensadvice/message-slack-action-2

[dependabot:actions] bump citizensadvice/message-slack-action from 1 to 2

Author: cnorthwood

.github/workflows/docker-image-scan.yml

@@ -75,7 +75,7 @@ jobs:
     if: failure()
     steps:
       - name: Notify Slack
-        uses: citizensadvice/message-slack-action@v1
+        uses: citizensadvice/message-slack-action@v2
         with:
           slack_bot_token: ${{ secrets.SLACK_BOT_TOKEN }}
           github_token: ${{ secrets.GITHUB_TOKEN }}