github: add docker publish action

.github/workflows/publish.yml

@@ -0,0 +1,54 @@
+# This workflow uses actions that are not certified by GitHub.
+# They are provided by a third-party and are governed by
+# separate terms of service, privacy policy, and support
+# documentation.
+
+# GitHub recommends pinning actions to a commit SHA.
+# To get a newer version, you will need to update the SHA.
+# You can also reference a tag or branch, but the action may change without warning.
+
+name: Publish Docker image
+
+on:
+  push:
+    branches:
+      - master
+
+jobs:
+  push_to_registry:
+    name: Push Docker image to Docker Hub
+    runs-on: ubuntu-latest
+    permissions:
+      packages: write
+      contents: read
+      attestations: write
+      id-token: write
+    strategy:
+      matrix:
+        release: [stretch, buster]
+    steps:
+      - name: Check out the repo
+        uses: actions/checkout@v4
+
+      - name: Log in to Docker Hub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+
+      - name: Build and push Docker image
+        id: push
+        uses: docker/build-push-action@v6
+        with:
+          context: ev3dev-${{ matrix.release }}
+          file: ev3dev-${{ matrix.release }}/debian-${{ matrix.release }}-cross.dockerfile
+          push: true
+          tags: ev3dev/debian-${{ matrix.release }}-cross:latest
+
+      - name: Generate artifact attestation
+        uses: actions/attest-build-provenance@v1
+        with:
+          subject-name: index.docker.io/ev3dev/debian-${{ matrix.release }}-cross
+          subject-digest: ${{ steps.push.outputs.digest }}
+          push-to-registry: true
+