Add support for flat config #1746

	name: CI

	on:
	push:
	branches: [master]
	pull_request:
	branches: [master]

	jobs:
	lint:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: actions/setup-node@v4
	- name: Install Packages
	run: npm ci
	- name: Build
	run: npm run build
	- name: Lint
	run: npm run lint
	test:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	node: [18.x, 20.x]
	eslint: [8, ^9.0.0-0]
	steps:
	- uses: actions/checkout@v4
	- name: Use Node.js ${{ matrix.node }}
	uses: actions/setup-node@v4
	with:
	node-version: ${{ matrix.node }}
	- name: Install ESLint ${{ matrix.eslint }}
	# We use --legacy-peer-deps because we get a lot of dependency warnings when installing eslint v9-alpha.
	run: npm i -D eslint@${{ matrix.eslint }} --legacy-peer-deps
	- name: Install Packages
	# run: npm ci
	# We use `npm i` because there is an error regarding dependencies when installing eslint v9-alpha.
	run: npm i -f
	- name: Test
	run: npm test
	test-and-coverage:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: actions/setup-node@v4
	- name: Install Packages
	run: npm ci
	- name: Test
	run: npm run test:nyc
	- name: Coveralls GitHub Action
	uses: coverallsapp/github-action@v2
	with:
	github-token: ${{ secrets.GITHUB_TOKEN }}
	update:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- uses: actions/setup-node@v4
	- name: Install Packages
	run: npm ci
	- name: Build
	run: npm run build
	- name: Update
	run: npm run update
	- name: Check changes
	run: \|
	git add --all && \
	git diff-index --cached HEAD --stat --exit-code

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