fix: mastodon secret used workflow, not action (#267)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

- **Chores**
- Updated the release announcement workflow to use an updated Mastodon
integration and improved token handling.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Author: cmeesters

.github/workflows/announce-release.yml

@@ -16,9 +16,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Post to Mastodon
-        uses: snakemake/[email protected].3
+        uses: snakemake/[email protected].4
 
         with:
+          access-token: ${{ secrets.MASTODONBOT }}
           message: |
             Beep, Beep - I am your friendly #Snakemake release announcement bot.