Go updates (modules and add go1.21 to the CI) #19

	name: vet and build

	on:
	pull_request:
	branches_ignore: []

	jobs:
	build:
	runs-on: ubuntu-latest
	strategy:
	matrix:
	go: ['1.17', '1.18', '1.19', '1.20', '1.21']

	name: Documentation and Linting
	steps:

	- uses: actions/checkout@v2
	with:
	path: go/src/github.com/vbatts/git-validation

	# commit for v1 release
	- uses: actions/setup-go@0caeaed6fd66a828038c2da3c0f662a42862658f
	with:
	go-version: ${{ matrix.go }}

	- name: vet and build
	env:
	GOPATH: /home/runner/work/git-validation/git-validation/go
	run: \|
	set -x
	export PATH=$GOPATH/bin:$PATH
	cd go/src/github.com/vbatts/git-validation
	go run mage.go -v vet build test
	./git-validation -run DCO,short-subject,dangling-whitespace -v
	./git-validation -run DCO,short-subject,dangling-whitespace -v -range ${GITHUB_SHA}..HEAD

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