rename Containerfile -> Containerfile.multistage, update README.md #13

	---
	name: Build demoapp-backend

	# Events: https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows
	on:
	push:
	branches:
	- main
	- release/.*
	paths-ignore:
	- '**.md'
	workflow_dispatch:
	jobs:
	lint:
	uses: ./.github/workflows/lint.yml # Workflow calls need to be executed as jobs
	with:
	yaml: true
	sonarqube-scan:
	runs-on: ubuntu-latest
	steps:
	- name: SonarQube Scan
	uses: sonarsource/sonarqube-scan-action@master
	with:
	# github context: https://docs.github.com/en/actions/learn-github-actions/contexts#github-context
	args: >
	-Dsonar.organization=${{ github.repository_owner }}
	-Dsonar.projectKey=demoapp-backend
	env:
	SONAR_TOKEN: ${{ secrets.SONAR_TOKEN }}
	SONAR_HOST_URL: https://sonarcloud.io/
	build:
	needs: sonarqube-scan
	runs-on: ubuntu-latest
	steps:
	- name: Clone
	uses: actions/checkout@v4 # https://github.com/marketplace/actions/checkout
	- name: Set up QEMU
	uses: docker/setup-qemu-action@v3 # https://github.com/marketplace/actions/docker-setup-qemu
	- name: Set up Docker Buildx
	uses: docker/setup-buildx-action@v3 # https://github.com/marketplace/actions/docker-setup-buildx
	- name: Build container image
	uses: docker/build-push-action@v5 # https://github.com/marketplace/actions/build-and-push-docker-images
	with:
	context: .
	file: Containerfile
	push: false
	tags: demoapp-backend
	cache-from: type=gha
	cache-to: type=gha,mode=max

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