Fix check-libs charmcraft channel (#818)

Author: carlcsaposs-canonical

.github/workflows/lib-check.yaml

@@ -29,6 +29,7 @@ jobs:
       - name: Check libs
         uses: canonical/charming-actions/[email protected]
         with:
+          charmcraft-channel: latest/beta/data-platform  # TODO: remove after charmcraft 3.3 stable release
           credentials: "${{ secrets.CHARMHUB_TOKEN }}"
           github-token: "${{ secrets.GITHUB_TOKEN }}"