`notation` のページのコード例の修正 #1139

	# see: https://github.com/rami3l/plfl/blob/master/.github/workflows/ci.yml
	name: CI

	# https://docs.github.com/en/actions/using-jobs/using-concurrency#example-only-cancel-in-progress-jobs-or-runs-for-the-current-workflow
	concurrency:
	group: ${{ github.workflow }}-${{ github.ref }}
	cancel-in-progress: true

	on:
	pull_request:
	branches:
	- main
	push:
	branches:
	- main
	workflow_dispatch:

	jobs:
	ubuntu_build:
	runs-on: ubuntu-latest
	steps:
	- name: checkout
	uses: actions/checkout@v4

	- name: lean action
	uses: leanprover/lean-action@v1
	with:
	build-args: "--log-level=warning"

	- name: lean action (warning as fail)
	uses: leanprover/lean-action@v1
	with:
	build-args: "--fail-level=warning"

	# Lean の更新により Windows 環境でだけビルドが壊れる可能性もあるので、
	# 念のために Windows 環境でもビルドを行う
	windows_build:
	runs-on: windows-latest
	# 失敗することはめったにないので PR 時にはチェックしない
	if: github.ref == 'refs/heads/main'
	steps:
	- name: checkout
	uses: actions/checkout@v4

	- name: lean action
	uses: leanprover/lean-action@v1
	with:
	build-args: "--log-level=error"

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