--ephemeral should use a non-default port

[carver]

If a port isn't explicitly specified, and the --ephemeral flag is set, then we should set a different port.

The main annoyance of using the default port is if you use --ephemeral twice in a row, or run ephemeral and then a non-ephemeral run. Because a bunch of former peers are contacting you on that port, expecting a different public key, your logs get flooded with warnings about incoming packets that can't be decoded. (This happened on Joseph Cook's first contact with trin)

Maybe chose the port based on the generated node-id, to help spread it out across runs? Maybe randomize the port?

[1010adigupta]

I can take up this, you can assign me

[KaydenML]

Fixed this issue in this PR
#1124