feat: add tparallel linter to improve handling parallel tests

This linter both prevents parallel test races as well as
suggests parallel tests where appropriate:
See: https://github.com/moricho/tparallel

Signed-off-by: Milos Gajdos <milosthegajdos@gmail.com>

registry/storage/driver/errors_test.go

@@ -33,6 +33,7 @@ func TestErrorFormat(t *testing.T) {
 }
 
 func TestErrors(t *testing.T) {
+	t.Parallel()
 	drvName := "foo"
 
 	testCases := []struct {