Update to 1.21. Fix #62 #220

	# Automatically build the project and run any configured tests for every push
	# and submitted pull request. This can help catch issues that only occur on
	# certain platforms or Java versions, and provides a first line of defence
	# against bad commits.
	name: build
	on: [pull_request, push]
	jobs:
	build:
	runs-on: ubuntu-latest
	steps:
	- name: checkout repository
	uses: actions/checkout@v2
	- name: setup jdk 21
	uses: actions/setup-java@v4
	with:
	distribution: temurin
	java-version: 21
	# to cache gradle files
	- name: Setup Gradle
	uses: gradle/actions/setup-gradle@v3
	with:
	gradle-home-cache-cleanup: true
	dependency-graph: generate-and-submit
	# Already needs to be executable, so the dirty check is correct
	# - name: make gradle wrapper executable
	# if: ${{ runner.os != 'Windows' }}
	# run: chmod +x ./gradlecw
	- name: build
	run: ./gradlecw build
	- name: capture build artifacts
	uses: actions/upload-artifact@v2
	with:
	name: Artifacts
	path: 'versions/*/build/libs/.jar'
	# - name: Test Report
	# uses: dorny/test-reporter@v1
	# if: success() \|\| failure()
	# with:
	# name: JUnit Tests
	# path: '*/build/test-results/test/TEST-.xml'
	# reporter: java-junit

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