cli: remove uses of deprecated registry.SetCertsDir

Starting with [moby@b633c4c], the registry package handles this internally
and there's no longer a need to set the path manually for rootlessKit

[moby@b633c4c]: b633c4cc33

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Signed-off-by: Paweł Gronowski <pawel.gronowski@docker.com>

cli/cobra.go

@@ -3,15 +3,12 @@ package cli
 import (
 	"fmt"
 	"os"
-	"path/filepath"
 	"sort"
 	"strings"
 
 	"github.com/docker/cli/cli-plugins/metadata"
 	"github.com/docker/cli/cli/command"
 	cliflags "github.com/docker/cli/cli/flags"
-	"github.com/docker/docker/pkg/homedir"
-	"github.com/docker/docker/registry"
 	"github.com/fvbommel/sortorder"
 	"github.com/moby/term"
 	"github.com/morikuni/aec"
@@ -62,13 +59,6 @@ func setupCommonRootCommand(rootCmd *cobra.Command) (*cliflags.ClientOptions, *c
 		"docs.code-delimiter": `"`, // https://github.com/docker/cli-docs-tool/blob/77abede22166eaea4af7335096bdcedd043f5b19/annotation/annotation.go#L20-L22
 	}
 
-	// Configure registry.CertsDir() when running in rootless-mode
-	if os.Getenv("ROOTLESSKIT_STATE_DIR") != "" {
-		if configHome, err := homedir.GetConfigHome(); err == nil {
-			registry.SetCertsDir(filepath.Join(configHome, "docker/certs.d"))
-		}
-	}
-
 	return opts, helpCommand
 }