chore(deps): update slackapi/slack-github-action action to v2.1.1

Author: renovate[bot]

.github/actions/release-slack-bot/action.yml

@@ -11,7 +11,7 @@ runs:
   using: "composite"
   steps:
     # TODO: use python exec instead
-    - uses: slackapi/[email protected].0
+    - uses: slackapi/[email protected].1
       with:
         method: chat.postMessage
         token: ${{ inputs.slack-token }}