Use KO for building and pushing images

This uses the ko tool to build and push images to ghcr.io. Since
building with docker has some issues lately.

Signed-off-by: Chmouel Boudjnah <[email protected]>

Author: chmouel

.github/workflows/container.yaml

@@ -0,0 +1,54 @@
+name: Create and publish a Docker image to ghcr on main and nightly with ko
+
+on:
+  push:
+    branches:
+      - main
+      - nightly
+    paths:
+      - "**.go"
+  pull_request:
+    paths:
+      - "**.yaml"
+
+env:
+  REGISTRY: ghcr.io
+
+jobs:
+  build-and-push-image:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+
+    concurrency:
+      group: ${{ github.workflow }}-${{ github.ref }}-${{ matrix.platform }}
+      cancel-in-progress: true
+
+    strategy:
+      matrix:
+        platform: [linux/amd64, linux/arm64]
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up Go
+        uses: actions/setup-go@v5
+        with:
+          go-version-file: "go.mod"
+
+      - uses: ko-build/[email protected]
+
+      - name: Build and push images
+        shell: bash
+        run: |
+          set -x
+          if [[ ${{ github.ref }} == refs/pull/* ]]; then
+            tag=pr-$(echo ${{ github.ref }} | cut -c11-|sed 's,/merge,,')
+          else
+            tag=$(echo ${{ github.ref }} | cut -c11-)
+          fi
+          for image in ./cmd/*;do
+            ko build -B -t ${tag} --platform=${{ matrix.platform }} ${image}
+          done