Add CONTRIBUTING.md #157

	# Copyright 2021 lbruun.net.
	#
	# Licensed under the Apache License, Version 2.0 (the "License");
	# you may not use this file except in compliance with the License.
	# You may obtain a copy of the License at
	#
	# http://www.apache.org/licenses/LICENSE-2.0
	#
	# Unless required by applicable law or agreed to in writing, software
	# distributed under the License is distributed on an "AS IS" BASIS,
	# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	# See the License for the specific language governing permissions and
	# limitations under the License.

	name: CI workflow for Pre-Liquibase

	on:
	push:
	pull_request:
	workflow_dispatch:

	jobs:
	build-all:
	name: Build
	runs-on: ubuntu-latest
	steps:
	- name: Checkout
	uses: actions/checkout@v2
	with:
	persist-credentials: false

	- name: Setup Java
	uses: actions/setup-java@v2
	with:
	distribution: 'zulu'
	java-version: '17'

	- name: Build
	run: mvn clean package

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