gha: another docker build output fix

Author: haarg

.github/workflows/build-container.yml

@@ -34,7 +34,7 @@ jobs:
           ghcr_username: ${{ github.repository_owner }}
           ghcr_password: ${{ secrets.GITHUB_TOKEN }}
       - name: Update deployed image
-        if: steps.find-tag-names.outputs.latest
+        if: ${{ fromJSON(steps.build-push.outputs.tag-fq).latest }}
         uses: metacpan/metacpan-actions/update-deployed-tag@master
         with:
           token: ${{ steps.app-token.outputs.token }}