fix(ci): use fully qualified snap channel names for promote

Newer snapcraft requires 'latest/edge' instead of 'edge' when
using --yes with the promote command.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.github/workflows/studio-publish.yml

@@ -450,7 +450,7 @@ jobs:
       - name: Move release snap from edge to stable
         continue-on-error: true
         run: |
-          snapcraft promote beekeeper-studio --from-channel "edge" --to-channel "stable" --yes
+          snapcraft promote beekeeper-studio --from-channel "latest/edge" --to-channel "latest/stable" --yes
 
   publish_repositories:
     needs: [release, create_draft_release, identify_channel]