Fix tagging of frosting

Author: chrissearle

.github/workflows/release.yaml

@@ -36,10 +36,10 @@ jobs:
         run: |
           docker buildx imagetools create \
             --tag ghcr.io/javabin/frosting:release \
-            ghcr.io/javabin/cupcake:staging
+            ghcr.io/javabin/frosting:staging
 
       - name: Create version tag from staging frosting
         run: |
           docker buildx imagetools create \
             --tag ghcr.io/javabin/frosting:${{ github.ref_name }} \
-            ghcr.io/javabin/cupcake:staging
+            ghcr.io/javabin/frosting:staging