Update test matrix on CI

[Goooler]

Reflects

shadow/.github/workflows/build.yml

Lines 11 to 36 in 3e44233

	build:
	name: OS=${{ matrix.os }}, Java=${{ matrix.java }}, Gradle=${{ matrix.gradle }}
	strategy:
	matrix:
	os: [ ubuntu-24.04-arm ]
	# Always test on the latest version and some LTS.
	java: [ 17, 24 ]
	# Test on the minimum Gradle version and the latest.
	gradle: [ 9.0.0, current ]
	include:
	# We just test one JDK version on Windows.
	- os: windows-11-arm
	gradle: 9.0.0
	java: 21
	- os: windows-11-arm
	gradle: current
	java: 21
	runs-on: ${{ matrix.os }}
	steps:
	- uses: actions/checkout@v5
	- uses: actions/setup-java@v5
	with:
	distribution: 'zulu'
	java-version: ${{ matrix.java }}
	- uses: gradle/actions/setup-gradle@v5
	- run: ./gradlew build "-PtestGradleVersion=${{ matrix.gradle }}" --stacktrace -x lint

[Copilot]

Pull Request Overview

Updates the CI test matrix configuration to align with the GradleUp/shadow project's workflow, focusing on ARM-based Ubuntu runners with selective Windows testing and refined Java version coverage.

Key changes:

• Switched primary OS from multiple platforms to ARM-based Ubuntu (ubuntu-24.04-arm)
• Reduced Java version matrix from [17, 21, 25] to [17, 25]
• Added selective Windows testing via include matrix for specific Java/Gradle combinations

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