Add binder progress and logs to status tab

[fonsp]

When you click "Edit or run this notebook" on an HTML export, then Binder, it can take some time to start. Like we discovered in the past, long waiting times should be broken down into individual steps, and more information is good! E.g. #2399 and #2498

This PR uses the GUI from #2399 during the binder launch to show the current step (we can break a binder launch down into 5 steps), and we also relay the binder logs. The logs don't contain anything useful to the user, but they give a true sense of progress. (Rather than a fake loading bar 😇)

I used the backend_launch_phase for the subtasks of the backend launch, and I capture the JSON logs from the streaming mybinder.org API as logs in the little terminal, similar to #2498

[github-actions]

Try this Pull Request!

Open Julia and type:

julia> import Pkg
julia> Pkg.activate(temp=true)
julia> Pkg.add(url="https://github.com/fonsp/Pluto.jl", rev="binder-status-tab")
julia> using Pluto

[fonsp]

Here is a full binder launch, video file is a bit broken

cca52e1d-c1a0-4af6-b0fc-45dd979cd894.mp4

[fonsp]

@pankgeorg Tthis feature should already work on JH if you set the backend_launch_phase during the boot (like the local and binder backends do).

Like the binder backend, it might be nice to include the logs if they are easily available to the frontend, use https://github.com/fonsp/Pluto.jl/pull/2523/files#diff-c0a453bced0e2ce81412403f646a1e2bbfd19300fab615ce77b039a417c82dceR109-R113 to set the value of the terminal. You could also use this to print something like

Launching a 4-core 8GB computer on thisandthat account. Go to asdf.com/asdf to see all your job launches!

[fonsp]

Updated PR description