Build and publish to ghcr.io on merge

This will build and publish to GitHub Packages on every time code
is submitted to repository.

.github/workflows/docker-image.yml

@@ -0,0 +1,55 @@
+name: Build
+
+on:
+  push:
+    branches:
+      - 'master'
+    tags:
+      - 'v*.*.*'
+  pull_request:
+    branches:
+      - 'master'
+
+permissions:
+  packages: write
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v1
+      - name: Set up Docker Buildx
+        id: buildx
+        uses: docker/setup-buildx-action@v1
+      - name: Login to GHCR
+        if: github.event_name != 'pull_request'
+        uses: docker/login-action@v1
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+      - name: Docker meta
+        id: metadata
+        uses: docker/metadata-action@v3
+        with:
+          images: |
+            ghcr.io/gi-wg2/gophish
+          tags: |
+            type=schedule
+            type=ref,event=branch
+            type=ref,event=pr
+            type=semver,pattern={{version}}
+            type=semver,pattern={{major}}.{{minor}}
+            type=semver,pattern={{major}}
+            type=sha
+      - name: Build and push
+        uses: docker/build-push-action@v2
+        with:
+          context: .
+          platforms: linux/amd64,linux/arm/v7,linux/arm64/v8
+          push: ${{ github.event_name != 'pull_request' }}
+          tags: ${{ steps.metadata.outputs.tags }}
+          labels: ${{ steps.metadata.outputs.labels }}