VSC: Mark extension ports as "ignored"

[schickling]

Issue description or question

Currently when starting Wallaby in VSC, I'm seeing the following ports open notification popups. This "new port available" popup feature is generally very useful but not in the case of Wallaby since its rather an "implementation detail".

It seems like it will soon be possible (see https://github.com/microsoft/vscode-remote-release/issues/4046) for both extension authors and users to mark ports as ignored: true which will be a great fit for this issue.

[smcenlly]

Wallaby uses both fixed and dynamic port ranges for a number of its operations. We could mark the fixed ports as "known" but I'm not sure this will solve your problem.