Added Self-Hosted Docker Image build&push workflow

Author: krll-dev

.github/workflows/docker-build-self-hosted.yml

@@ -0,0 +1,18 @@
+name: Build & Push Docker Image
+on:
+  push:
+    branches: [ master ]
+
+jobs:
+  build-and-push:
+    runs-on: [ self-hosted, docker-builder ]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Build & Push
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          push: true
+          tags: kirillesau/spring-demo-application:self-hosted