I don't understand the point of checking it from client side. It's a 100% server side problem. I kind of expected some replies like "check this and that config file and log file and post log output here" something.
I've tried https://check-your-website.server-daten.de/ This site does a lot of stuff checking certificates and DNS records, it won't help troubleshoot Apache configuration.
I have a weird feeling about this really. Looks like you don't understand the nature of the problem. It's a problem with Apache config. It's supposed to generate the 301 header which it does not. There's no point checking it at browser side.