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

weed/util/http/client/http_client_opt.go

@@ -0,0 +1,18 @@
+package client
+
+import (
+	"net"
+	"time"
+)
+
+type HttpClientOpt = func(clientCfg *HTTPClient)
+
+func AddDialContext(httpClient *HTTPClient) {
+	dialContext := (&net.Dialer{
+		Timeout:   10 * time.Second,
+		KeepAlive: 10 * time.Second,
+	}).DialContext
+
+	httpClient.Transport.DialContext = dialContext
+	httpClient.Client.Transport = httpClient.Transport
+}