feat(workflows): Add webinstall workflow to push image (#1336)

Reviewed-by: Antoine Cotten <antoine@unikraft.io>
Approved-by: Antoine Cotten <antoine@unikraft.io>

.github/workflows/webinstall.yaml

@@ -0,0 +1,31 @@
+name: tools/webinstall
+
+on:
+  push:
+    branches: [stable]
+    paths:
+      - 'tools/webinstall/**'
+
+jobs:
+  myself-push:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Login to Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{github.actor}}
+          password: ${{secrets.GITHUB_TOKEN}}
+
+      - name: Build & Push OCI Image
+        uses: docker/build-push-action@v5
+        with:
+          push: true
+          tags: ghcr.io/unikraft/kraftkit/webinstall:latest
+          platforms: linux/amd64
+          file: ./tool/webinstall/Dockerfile
+          secrets: |
+            GIT_AUTH_TOKEN=${{ secrets.GITHUB_TOKEN }}