Set up sbt explicitly because it will be dropped in ubuntu-24.04 (#511) #1446

	name: Build all samples
	on:
	push:
	branches:
	- main
	- 'r5.*'
	pull_request:
	branches:
	- '*'
	jobs:
	linux:
	name: Linux
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
	- name: 'Set up JDK 21'
	uses: actions/setup-java@7a6d8a8234af8eb26422e24e3006232cccaa061b # v4
	with:
	java-version: 21
	distribution: temurin
	- uses: sbt/setup-sbt@v1
	- name: 'Build all samples using JShell'
	run: java src/Builder.java
	- name: 'Check automation for updating versions'
	run: java src/Updater.java 42
	if: github.repository == 'junit-team/junit5-samples' && github.ref == 'refs/heads/main'
	- name: 'Check automation for injecting a staging repository'
	run: java src/StagingRepoInjector.java https://example.org/service/local/repositories/orgjunit-1234/content
	if: github.repository == 'junit-team/junit5-samples' && github.ref == 'refs/heads/main'

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