Added tls for http clients (#5766)

* Added global http client

* Added Do func for global http client

* Changed the code to use the global http client

* Fix http client in volume uploader

* Fixed pkg name

* Fixed http util funcs

* Fixed http client for bench_filer_upload

* Fixed http client for stress_filer_upload

* Fixed http client for filer_server_handlers_proxy

* Fixed http client for command_fs_merge_volumes

* Fixed http client for command_fs_merge_volumes and command_volume_fsck

* Fixed http client for s3api_server

* Added init global client for main funcs

* Rename global_client to client

* Changed:
- fixed NewHttpClient;
- added CheckIsHttpsClientEnabled func
- updated security.toml in scaffold

* Reduce the visibility of some functions in the util/http/client pkg

* Added the loadSecurityConfig function

* Use util.LoadSecurityConfiguration() in NewHttpClient func

unmaintained/diff_volume_servers/diff_volume_servers.go

@@ -20,6 +20,7 @@ import (
 	"github.com/seaweedfs/seaweedfs/weed/storage/types"
 	"github.com/seaweedfs/seaweedfs/weed/util"
 	"google.golang.org/grpc"
+	util_http "github.com/seaweedfs/seaweedfs/weed/util/http"
 )
 
 var (
@@ -40,7 +41,8 @@ var (
 */
 func main() {
 	flag.Parse()
-
+	util_http.InitGlobalHttpClient()
+	
 	util.LoadSecurityConfiguration()
 	grpcDialOption = security.LoadClientTLS(util.GetViper(), "grpc.client")