Create tagged Docker image on new tag/release

.github/workflows/dockerize.yml

@@ -0,0 +1,47 @@
+name: dockerize
+
+on:
+  push:
+    tags:
+      - "*"
+    branches:
+      - master
+    paths:
+      - src/khoj/**
+      - config/**
+      - setup.py
+      - Dockerfile
+      - docker-compose.yml
+      - .github/workflows/dockerize.yml
+  workflow_dispatch:
+
+env:
+  DOCKER_IMAGE_TAG: ${{ github.ref == 'refs/heads/master' && 'latest' || github.ref_name }}
+
+jobs:
+  build:
+    name: Build Docker Image, Push to Container Registry
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout Code
+        uses: actions/checkout@v2
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1
+
+      - name: Login to GitHub Container Registry
+        uses: docker/login-action@v1
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.PAT }}
+
+      - name: Build and Push Docker Image
+        uses: docker/build-push-action@v2
+        with:
+          context: .
+          file: Dockerfile
+          push: true
+          tags: ghcr.io/${{ github.repository }}:${{ env.DOCKER_IMAGE_TAG }}
+          build-args: |
+            PORT=8000