Add `docker-build` action to take advantage of caching and use sharding #906

	name: CI Tests

	on: [push, pull_request]

	jobs:

	test:

	runs-on: ubuntu-latest
	strategy:
	matrix:
	shard: [1, 2, 3, 4, 5]

	steps:
	- name: Checkout
	uses: actions/checkout@v2

	- name: Set up JDK 11
	uses: actions/setup-java@v2
	with:
	java-version: '11'
	distribution: 'adopt'

	- name: Setup Nextflow ${{ matrix.nextflow }}
	uses: nf-core/setup-nextflow@v1
	with:
	version: "latest-edge"

	- name: Install nf-test
	run: \|
	wget -qO- https://code.askimed.com/install/nf-test \| bash -s 0.9.0-rc2
	sudo mv nf-test /usr/local/bin/

	- name: Set up Docker Buildx
	uses: docker/setup-buildx-action@v3

	- name: Build Docker
	uses: docker/build-push-action@v5
	with:
	context: .
	push: false
	load: true
	tags: "genepi/nf-gwas"
	cache-from: type=gha
	cache-to: type=gha,mode=max

	- name: Run Tests (Shard ${{ matrix.shard }}/${{ strategy.job-total }})
	run: nf-test test --ci --shard ${{ matrix.shard }}/${{ strategy.job-total }}

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