Make use of correct variable

Author: CodeDead

.github/workflows/release.yml

@@ -31,7 +31,7 @@ jobs:
         with:
           context: .
           push: true
-          tags: ${{ env.DOCKERHUB_REPO }}:latest
+          tags: ${{ vars.DOCKERHUB_REPO }}:latest
 
   gh-release:
     if: startsWith(github.ref, 'refs/tags/')