Update Yarn to v4 #24

	name: CI

	on:
	push:
	branches:
	- master
	pull_request:
	branches: '*'

	jobs:
	lint:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- name: Install node
	uses: actions/setup-node@v1
	with:
	node-version: 14
	- name: Cache
	uses: actions/cache@v2
	id: cache
	with:
	path: '**/node_modules'
	key: yarn-v1-${{ hashFiles('**/yarn.lock') }}
	- name: Install
	run: yarn --immutable
	if: steps.cache.outputs.cache-hit != 'true'
	- name: Lint
	run: yarn lint

	build:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v2
	- name: Install node
	uses: actions/setup-node@v1
	with:
	node-version: 14
	- name: Cache
	uses: actions/cache@v2
	id: cache
	with:
	path: '**/node_modules'
	key: yarn-v1-${{ hashFiles('**/yarn.lock') }}
	- name: Install
	run: yarn --immutable
	if: steps.cache.outputs.cache-hit != 'true'
	- name: Build
	run: yarn build

	# test:
	# runs-on: ubuntu-latest
	# steps:
	# - uses: actions/checkout@v2
	# - name: Install node
	# uses: actions/setup-node@v1
	# with:
	# node-version: 14
	# - name: Cache
	# uses: actions/cache@v2
	# id: cache
	# with:
	# path: "**/node_modules"
	# key: yarn-v1-${{ hashFiles('**/yarn.lock') }}
	# - name: Install
	# run: yarn --immutable
	# if: steps.cache.outputs.cache-hit != 'true'
	# - name: Compile
	# run: yarn build
	# - name: Test
	# run: yarn test

	env:
	CI: true

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