Revert "Fix TestAttachExitCode"

This reverts commit 3acd4904bf.

Signed-off-by: Andrew Hsu <andrewhsu@docker.com>

components/cli/e2e/container/attach_test.go

@@ -1,30 +0,0 @@
-package container
-
-import (
-	"strings"
-	"testing"
-
-	"github.com/docker/cli/e2e/internal/fixtures"
-	"github.com/gotestyourself/gotestyourself/icmd"
-)
-
-func TestAttachExitCode(t *testing.T) {
-	containerID := runBackgroundContainsWithExitCode(t, 21)
-
-	result := icmd.RunCmd(
-		icmd.Command("docker", "attach", containerID),
-		withStdinNewline)
-
-	result.Assert(t, icmd.Expected{ExitCode: 21})
-}
-
-func runBackgroundContainsWithExitCode(t *testing.T, exitcode int) string {
-	result := icmd.RunCmd(shell(t,
-		"docker run -d -i --rm %s sh -c 'read; exit %d'", fixtures.AlpineImage, exitcode))
-	result.Assert(t, icmd.Success)
-	return strings.TrimSpace(result.Stdout())
-}
-
-func withStdinNewline(cmd *icmd.Cmd) {
-	cmd.Stdin = strings.NewReader("\n")
-}