update slack helper

Author: akerl

.github/workflows/build.yml

@@ -35,7 +35,7 @@ jobs:
         GITHUB_TOKEN: ${{ github.token }}
     - name: Post to a Slack channel
       if: ${{ failure() }}
-      uses: slackapi/slack-github-action@v1.18.0
+      uses: slackapi/slack-github-action@v1.23.0
       env:
         SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
         SLACK_WEBHOOK_TYPE: INCOMING_WEBHOOK