Bump actions/setup-go from 3 to 4 #6

	name: Tests

	on: [push, pull_request]

	jobs:
	test:
	runs-on: ubuntu-latest
	name: Go test
	steps:
	- uses: actions/checkout@master
	- uses: actions/setup-go@v4
	with:
	go-version: '1.18.1'
	- run: \|
	go test ./...
	build:
	runs-on: ubuntu-latest
	name: Go build
	steps:
	- uses: actions/checkout@master
	- uses: actions/setup-go@v4
	with:
	go-version: '1.18.1'
	- run: \|
	go build -mod=vendor -o operator github.com/movetokube/postgres-operator/cmd/manager
	file operator

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