Feature: Add a possibility to specify a port

[marfrede]

If an incorrect URL is opened, please provide the following so we can write a test:

Example clone url:

ssh://git@xyz.abc.de:23/frontend.git

Example branch name:

my-branch

Expected web URL:

https://xyz.abc.de:8080/frontend/tree/story/my-branch

But the URL being actually opened is:

https://xyz.abc.de/ISP6/frontend/tree/story/100263-machine-cards-printing-overview
(so port 80 is being used as standard of course https://xyz.abc.de:80/ISP6/frontend/tree/story/100263-machine-cards-printing-overview)

It would be nice to have a port option to use git open --port 8080

It would be nice to have the option to set a port somewhere at the configs