UI: Fix tray icon showing up on startup even if off

Apparently certain versions of Qt have a bug where the tray icon's
internal "visible" variable is set to false despite the fact that it
still shows.  Calling show() first before calling hide() sets the
internal boolean value and fixes the issue with the hide call.

UI/window-basic-main.cpp

@@ -6817,6 +6817,7 @@ void OBSBasic::SystemTrayInit()
 	trayMenu->addAction(sysTrayReplayBuffer);
 	trayMenu->addAction(exit);
 	trayIcon->setContextMenu(trayMenu);
+	trayIcon->show();
 
 	if (outputHandler && !outputHandler->replayBuffer)
 		sysTrayReplayBuffer->setEnabled(false);