Fix and test Java 8 compatibility when building from Java 21 or later. #766

	name: Build
	on: [push, pull_request]
	jobs:
	build:
	strategy:
	matrix:
	java: [17-jdk, 21-jdk]
	runs-on: ubuntu-22.04
	container:
	image: eclipse-temurin:${{ matrix.java }}
	options: --user root
	steps:
	- uses: actions/checkout@v4
	- run: ./gradlew build publishToMavenLocal --stacktrace --warning-mode fail
	- uses: actions/upload-artifact@v3
	with:
	name: Artifacts
	path: build/libs/

	client_test:
	runs-on: ubuntu-22.04
	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: 0
	- uses: actions/setup-java@v3
	with:
	distribution: 'microsoft'
	java-version: '17'
	- name: Run Auto test Client
	uses: modmuss50/xvfb-action@v1
	with:
	run: ./gradlew :minecraft:minecraft-test:runProductionAutoTestClient --stacktrace --warning-mode=fail
	- uses: actions/upload-artifact@v3
	if: always()
	with:
	name: Client Test Screenshots
	path: minecraft/minecraft-test/run/screenshots

	smoke_test:
	runs-on: ubuntu-22.04
	steps:
	- uses: actions/checkout@v4
	with:
	fetch-depth: 0
	# Setup all the java versions we need
	# Java 8 and 17 for running the smoke tests, we build loader on 21
	- uses: actions/setup-java@v3
	with:
	distribution: 'corretto'
	java-version: '8'
	- uses: actions/setup-java@v3
	with:
	distribution: 'microsoft'
	java-version: '17'
	- uses: actions/setup-java@v3
	with:
	distribution: 'microsoft'
	java-version: '21'
	- run: ./gradlew :minecraft:minecraft-smoke-test:writeTestCommand --stacktrace --warning-mode fail
	- run: chmod +x runSmokeTests.sh
	- name: Run Smoke Tests
	uses: modmuss50/xvfb-action@v1
	with:
	run: ./runSmokeTests.sh

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