Only use Go 1.21 #371

	on: [push, pull_request]
	name: Build
	jobs:
	test:
	strategy:
	matrix:
	go-version: ['1.21.x']
	os: [ubuntu-latest, macos-latest]
	runs-on: ${{ matrix.os }}
	steps:
	- name: Install Go
	uses: actions/setup-go@v4
	with:
	stable: 'false'
	go-version: ${{ matrix.go-version }}
	- name: Checkout code
	uses: actions/checkout@v3
	- name: Test
	run: go test
	test-cache:
	runs-on: ubuntu-latest
	steps:
	- name: Install Go
	uses: actions/setup-go@v4
	with:
	go-version: '1.21.x'
	- name: Checkout code
	uses: actions/checkout@v3
	- uses: actions/cache@v2
	with:
	path: \|
	~/go/pkg/mod # Module download cache
	~/.cache/go-build # Build cache (Linux)
	~/Library/Caches/go-build # Build cache (Mac)
	key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
	restore-keys: \|
	${{ runner.os }}-go-
	- name: Test
	run: go test

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