added github action docker-image

.github/workflows/docker-image.yml

@@ -0,0 +1,38 @@
+name: Docker Image CI - Publish Docker image
+
+on:
+  push:
+    branches: [ "master" ]
+  pull_request:
+    branches: [ "master" ]
+
+jobs:
+  push_to_registry:
+    name: Push Docker image to Docker Hub
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Check out the repo
+      uses: actions/checkout@v3
+
+    - name: Log in to Docker Hub
+      uses: docker/login-action@v2
+      with:
+        username: ${{ secrets.DOCKER_USERNAME }}
+        password: ${{ secrets.DOCKER_PASSWORD }}
+
+    - name: Extract metadata (tags, labels) for Docker
+      id: meta
+      uses: docker/metadata-action@v4
+      with:
+        images: ${{ secrets.DOCKER_USERNAME }}/ssh-legacy
+        flavor: latest=true
+
+    - name: Build and push Docker image
+      uses: docker/build-push-action@v3
+      with:
+        context: .
+        push: true
+        tags: ${{ steps.meta.outputs.tags }}
+        labels: ${{ steps.meta.outputs.labels }}
+