Adapt Che Theia to upstream changes

[azatsarynnyy]

Is your task related to a problem? Please describe.

There's a WIP PR eclipse-theia/theia#8759 in upstream Theia that will bring the breaking changes related to mini-browser functionality. The /mini-browser Theia endpoint will be served on a dedicated host.
We need to adapt Che Theia to these changes.

Describe the solution you'd like

We need to declare another Che endpoint in Che Theia meta.yaml descriptor for exposing /mini-browser Theia's endpoint.
Like we did it for /webviews endpoint here.
And tell Che Theia to fetch the /mini-browser's content through a dedicated Che endpoint.

Describe alternatives you've considered

Additional context

Sub-tasks

• Declare a dedicated endpoint for exposing Che Theia /mini-browser content Declare a dedicated endpoint for exposing Che Theia mini-browser content che-plugin-registry#712
• Serve /mini-browser endpoint on a dedicated route Serve mini-browser endpoint on a dedicated route che-theia#930

[benoitf]

@azatsarynnyy what about declaring the new endpoint as soon as possible (in meta.yaml of plug-in registry) ?

[azatsarynnyy]

I'm going to open a PR after lunch 😉

[azatsarynnyy]

okay, opened a PR eclipse-che/che-plugin-registry#712
now, going to lunch 😄