Set up multiarch build

Author: ferrarimarco

.github/workflows/main.yml

@@ -21,6 +21,10 @@ jobs:
     needs: build
     runs-on: ubuntu-20.04
     steps:
+      - name: Setup Docker Buildx
+        uses: docker/setup-buildx-action@v1
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v1
       - name: Login to Docker Hub
         uses: docker/login-action@v1 
         with:
@@ -30,5 +34,7 @@ jobs:
         uses: docker/build-push-action@v2
         with:
           context: .
+          file: ./Dockerfile
+          platforms: linux/386,linux/amd64,linux/arm/v6,linux/arm/v7,linux/arm64,linux/ppc64le,linux/s390x
           push: true
-          tags: ferrarimarco/github-changelog-generator:latest
+          tags: githubchangeloggenerator/github-changelog-generator:latest

.github/workflows/push-tagged-image.yml

@@ -11,6 +11,10 @@ jobs:
     needs: build
     runs-on: ubuntu-20.04
     steps:
+      - name: Setup Docker Buildx
+        uses: docker/setup-buildx-action@v1
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v1
       - name: Login to Docker Hub
         uses: docker/login-action@v1 
         with:
@@ -20,5 +24,7 @@ jobs:
         uses: docker/build-push-action@v2
         with:
           context: .
+          file: ./Dockerfile
+          platforms: linux/386,linux/amd64,linux/arm/v6,linux/arm/v7,linux/arm64,linux/ppc64le,linux/s390x
           push: true
-          tags: ferrarimarco/github-changelog-generator:${{ github.event.release.tag_name }}
+          tags: githubchangeloggenerator/github-changelog-generator:${{ github.event.release.tag_name }}