fix(.github/workflows/test_deploy.yaml): correct cluster variable syn…

…tax to use proper GitHub Actions expression

The cluster variable in the GitHub Actions workflow was incorrectly set without the expression syntax `${{ }}`, which is necessary for evaluating GitHub secrets or environment variables. This change ensures that the `cluster` variable correctly references the `DEV_STAGING_CLUSTER` secret, allowing the deployment process to access the correct cluster configuration.

.github/workflows/test_deploy.yaml

@@ -8,7 +8,7 @@ jobs:
   deploy:
     uses: ./.github/workflows/deploy-app.yaml
     with:
-      cluster: ${{ secrets.DEV_STAGING_CLUSTER }}
+      cluster: secrets.DEV_STAGING_CLUSTER 
       cluster_state_storage: ${{ secrets.DEV_STAGING_KOPS_STATE_STORAGE }}
       repository: "https://github.com/dictyBase/static-server.git"
       image: goran