Add qemu-based multiarch build/test CI #154

	name: Build & Test

	on:
	push:
	branches: [ "main" ]
	pull_request:
	branches: [ "main" ]

	env:
	CARGO_TERM_COLOR: always

	jobs:
	build_test_i386:
	name: Build & Test i386
	runs-on: ubuntu-latest
	container:
	image: i386/rust:latest

	steps:
	# actions/checkout@v3 doesn't work in a i386 container: the GitHub runner
	# uses `node` that is installed on the host inside the container. The host
	# is (likely) running x86_64 and using a binary build for x86_64 inside a
	# i386 container just doesn't work.
	- uses: actions/checkout@v1

	- name: Build
	run: cargo build --release

	- name: Test
	run: cargo test --release

	# build_test_x86:
	# name: Build & Test X86
	# runs-on: ubuntu-latest

	# steps:
	# - uses: actions/checkout@v3

	# - name: Build
	# run: cargo build --release

	# - name: Test
	# run: cargo test --release

	# build_test_x86_avx2:
	# name: Build & Test X86 AVX2
	# runs-on: ubuntu-latest

	# steps:
	# - uses: actions/checkout@v3

	# - name: Switch to nightly rust
	# run: rustup default nightly

	# - name: Build
	# run: cargo build --release

	# - name: Test
	# run: cargo test --release

	# build_test_arm:
	# name: Build & Test ARM
	# runs-on: buildjet-2vcpu-ubuntu-2204-arm

	# steps:
	# - uses: actions/checkout@v3

	# - name: Build
	# run: cargo build --release

	# - name: Test
	# run: cargo test --release

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