[BUG] qbittorrent is not using the right port for listening

[8tomat8]

Describe the bug
tldr; According to this doc, qbittorrent has to be configured with the correct port, each time the gluetun connection is established.

I've experienced a lot of issues with seeding though VPN connection before enabling this setting.

To Reproduce

When VPN_PORT_FORWARDING_UP_COMMAND is not set, seeding is barely happening.

Expected behavior

All the active torrents should be activelly seeded.

Screenshots
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Platforms (please complete the following information):

• Docker compose version

Docker compose file

Here is a fix on my fork of the setup. 8tomat8@de5871e
I've diverged too much already to sync those. sorry :D

Additional context

Thanks for the project ❤️