chore: upgrade eslint to flat config #403

	name: Build

	on:
	push:
	branches: [main]
	pull_request:
	branches: [main]

	jobs:
	build:
	runs-on: ubuntu-latest

	strategy:
	matrix:
	node-version: [18, 20, 22]
	# See supported Node.js release schedule at https://nodejs.org/en/about/releases/
	graphql-version: [15, 16, 17.0.0-alpha.5]

	steps:
	- uses: actions/checkout@v4
	- name: Use Node.js ${{ matrix.node-version }}
	uses: actions/setup-node@v4
	with:
	node-version: ${{ matrix.node-version }}

	# https://github.com/actions/cache/blob/main/examples.md#node---yarn
	- name: Get yarn cache directory path
	id: yarn-cache-dir-path
	run: echo "dir=$(yarn cache dir)" >> $GITHUB_OUTPUT

	# https://github.com/actions/cache/blob/main/examples.md#node---yarn
	- name: Cache yarn packages
	uses: actions/cache@v4
	id: yarn-cache
	with:
	path: ${{ steps.yarn-cache-dir-path.outputs.dir }}
	key: ${{ runner.os }}-${{matrix.node-version}}-${{matrix.graphql-version}}-yarn-${{ hashFiles('yarn.lock') }}
	restore-keys: \|
	${{ runner.os }}-${{matrix.node-version}}-${{matrix.graphql-version}}-yarn-

	- name: Use GraphQL v${{matrix.graphql-version}}
	run: node ./scripts/match-graphql.js ${{matrix.graphql-version}}

	- name: Install from network when no cache hit
	if: steps.yarn-cache.outputs.cache-hit != 'true'
	run: yarn install --prefer-offline

	- name: Install from cache on cache-hit
	if: steps.yarn-cache.outputs.cache-hit == 'true'
	run: yarn install --offline

	- name: Format and Lint check
	run: yarn check-tsc && yarn lint && yarn build && yarn check-exports

	- name: Tests and Coverage
	run: yarn test --coverage

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