Define CI failure emails "body" content in markdown #17

	name: Lint and Test
	on: push
	permissions:
	contents: read
	jobs:
	build:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	php_version: [ '7.2', '7.3', '7.4', '8.0', '8.1' ]
	steps:
	- uses: actions/checkout@v4
	- name: Setup PHP
	uses: shivammathur/setup-php@v2
	with:
	php-version: ${{ matrix.php_version }}
	- name: Validate composer.json and composer.lock
	run: composer validate --strict
	- name: Cache Composer packages
	id: composer-cache
	uses: actions/cache@v3
	with:
	path: vendor
	key: ${{ runner.os }}-php-${{ matrix.php_version}}-${{ hashFiles('**/composer.lock') }}
	- name: Install dependencies
	run: composer install --prefer-source --no-progress
	- name: Run test suite
	run: composer run-script ci
	- name: Send mail on failure
	if: ${{ failure() }}
	uses: dawidd6/action-send-mail@v3
	with:
	server_address: smtp.gmail.com
	server_port: 465
	username: ${{secrets.CI_MAIL_USERNAME}}
	password: ${{secrets.CI_MAIL_PASSWORD}}
	to: [email protected]
	from: ${{ github.repository }} CI
	subject: CI job failed for ${{ github.repository }}
	convert_markdown: true
	html_body: file:///home/runner/work/Diff/Diff/.github/workflows/ci_failure_email.md

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