Upgrade to checkstyle 10.21.0 #337

	# Build workflow

	name: CI

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

	# Allows to run this workflow manually from the Actions tab
	workflow_dispatch:

	jobs:

	# Validate wrapper to prevent potential supply chain attack
	gradle-wrapper-validation:

	# Run on Ubuntu which consumes less minutes
	runs-on: ubuntu-latest

	name: Validate Gradle wrapper

	steps:
	- uses: actions/checkout@v4
	- uses: gradle/actions/wrapper-validation@v4

	build:

	# Many tests only pass on Windows
	runs-on: windows-latest

	strategy:
	matrix:
	java: [ '11', '21' ]

	name: Java ${{ matrix.java }} build

	steps:
	- uses: actions/checkout@v4

	# Set JDK
	- name: Set up JDK
	uses: actions/setup-java@v4
	with:
	java-version: ${{ matrix.java }}
	distribution: 'temurin'

	# Build
	- name: Build with Gradle
	run: >-
	./gradlew build

	# Upload test artifact
	- name: Upload test output
	uses: actions/upload-artifact@v4
	if: ${{ failure() }}
	with:
	name: test-output-${{ matrix.java }}
	path: \|
	echosvg-test/build/reports/tests/test/
	test-references/samples/*/candidate-variation/
	retention-days: 15
	overwrite: true

	# Generate modular javadocs
	- name: Modular javadocs
	if: ${{ success() }}
	run: ./gradlew modularJavadoc

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