Chore: remove DisableSyncLock setting, as it's not used anymore (#72680)

* rmeove DisableSyncLock setting, as it's not used anymore

* remove unused import

pkg/setting/setting.go

@@ -275,7 +275,6 @@ type Cfg struct {
 	AdminPassword                string
 	DisableLogin                 bool
 	AdminEmail                   string
-	DisableSyncLock              bool
 	DisableLoginForm             bool
 	// Not documented & not supported
 	// stand in until a more complete solution is implemented
@@ -1524,9 +1523,6 @@ func readAuthSettings(iniFile *ini.File, cfg *Cfg) (err error) {
 		cfg.TokenRotationIntervalMinutes = 2
 	}
 
-	// Debug setting unlocking frontend auth sync lock. Users will still be reset on their next login.
-	cfg.DisableSyncLock = auth.Key("disable_sync_lock").MustBool(false)
-
 	// Do not use
 	cfg.AuthConfigUIAdminAccess = auth.Key("config_ui_admin_access").MustBool(false)
 	cfg.AuthBrokerEnabled = auth.Key("broker").MustBool(true)