chore: Capitalize stage names in CI

.github/workflows/release.yml

@@ -17,19 +17,19 @@ jobs:
       matrix:
         image: ["mininet", "ryu"]
     steps:
-      - name: checkout
+      - name: Checkout
         uses: actions/checkout@v4
-      - name: set up qemu
+      - name: Set up QEMU
         uses: docker/setup-qemu-action@v3
-      - name: set up docker buildx
+      - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
-      - name: login to ghcr
+      - name: Login to GHCR
         uses: docker/login-action@v3
         with:
           registry: ghcr.io
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
-      - name: generate container metadata
+      - name: Generate Container Metadata
         id: metadata
         uses: docker/metadata-action@v5
         with: