UI: Immediately apply tray icon change on Apply

Rather than waiting until the user chooses OK or Cancel to update the
system tray icon status, update it when the user chooses Apply.

UI/window-basic-main.cpp

@@ -4768,8 +4768,6 @@ void OBSBasic::on_action_Settings_triggered()
 		settings.exec();
 	}
 
-	SystemTray(false);
-
 	settings_already_executing = false;
 
 	if (restart) {

UI/window-basic-settings.cpp

@@ -3151,11 +3151,14 @@ void OBSBasicSettings::SaveGeneralSettings()
 				"KeepReplayBufferStreamStops",
 				ui->keepReplayStreamStops->isChecked());
 
-	if (WidgetChanged(ui->systemTrayEnabled))
+	if (WidgetChanged(ui->systemTrayEnabled)) {
 		config_set_bool(GetGlobalConfig(), "BasicWindow",
 				"SysTrayEnabled",
 				ui->systemTrayEnabled->isChecked());
 
+		main->SystemTray(false);
+	}
+
 	if (WidgetChanged(ui->systemTrayWhenStarted))
 		config_set_bool(GetGlobalConfig(), "BasicWindow",
 				"SysTrayWhenStarted",