Check required environment variables in running tests.

checkenv.go

package checkenv

import (
	"os"
	"testing"
)

func CheckEnvs(t *testing.T, envs ...string) {
	t.Helper()

	for _, env := range envs {
		if v := os.Getenv(env); v == "" {
			t.Fatalf("environment variable `%s` is not defined", env)
		}
	}
}