Add L2 test container build workflow #1

	# yamllint disable rule:line-length
	name: Test for BuildEnv L2 container build

	on:
	push:
	branches:
	- main
	paths:
	- 'build-container/**'

	permissions:
	id-token: write
	attestations: write
	jobs:
	build:
	runs-on: ubuntu-latest

	steps:
	- name: Checkout
	uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4.1.7

	- name: Setup Go
	uses: actions/setup-go@0c52d547c9bc32b1aa3301fd7a9cb496313a4491 #v5
	with:
	go-version: 1.22.x

	- name: Install scai-gen CLI tools
	shell: bash
	run: \|
	go install github.com/in-toto/scai-demos/scai-gen@latest

	# Per BuildEnv L2, MUST automatically generate and distribute
	# signed reference values for the bootloader or equivalent, guest
	# kernel, build platform client, build executor, and root filesystem.
	- name: Attest container reference values
	id: ref-values
	uses: chkimes/image-attestation/.github/actions/attest-ref-values@main
	with:
	reference-path: 'build-container/*'

	- name: Build docker container
	id: build
	uses: docker/build-push-action@5cd11c3a4ced054e52742c5fd54dca954e0edd85 # v6.7.0
	with:
	context: "."
	file: "build-container/test-buildenv.dockerfile"
	tags: "test_l2:latest"

	- name: Generate SLSA Provenance
	id: slsa
	uses: actions/attest-build-provenance@6149ea5740be74af77f260b9db67e633f6b0a9a1 # v1.4.2
	with:
	subject-name: "test_l2"
	subject-digest: ${{ steps.build.outputs.digest }}

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