Add github action for docker publishing (#205)

* Add github action for docker publishing

.github/workflows/docker-build-push.yml

@@ -0,0 +1,42 @@
+name: Publish Docker image
+
+on:
+  push:
+    tags:
+      - '*'
+
+jobs:
+  publish-docker:
+
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Docker meta
+        id: meta
+        uses: docker/metadata-action@v3
+        with:
+          # list of Docker images to use as base name for tags
+          images: |
+            ayushsobti/kubemonkey
+          # Generate Docker tags based on the following events/attributes
+          tags: |
+            type=ref,event=tag
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v1
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1
+
+      - name: Login to DockerHub
+        uses: docker/login-action@v1 
+        with:
+          username: ${{ secrets.DOCKER_HUB_USERNAME }}
+          password: ${{ secrets.DOCKER_HUB_PASSWORD }}
+
+      - name: Build and push
+        uses: docker/build-push-action@v2
+        with:
+          platforms: linux/amd64
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}