Fix --startup.project to bypass opening dashboard

[somebody1234]

Pull Request Description

Fixes #6666

Important Notes

None

Checklist

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• The documentation has been updated, if necessary.
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[somebody1234]

@farmaazon you might want to test this to see whether it fixes the problem

[somebody1234]

this PR is intentionally based on an old develop, to make it easier to reproduce the problem. there should be no merge conflicts.

[farmaazon]

@farmaazon you might want to test this to see whether it fixes the problem

The issue is fixed 🎉

[PabloBuchu]

qa 🟢

[wdanilo]

Does it allow to go back to the dashboard? This option should be just a shorthand for opening a project, but everything should work just in a normal way, so going back to dashboard should be possible.

[somebody1234]

@wdanilo i decided not to do that because it was much simpler this way - but i can open a new PR to add the correct behavior soon

[wdanilo]

There are 2 problems with the current solution:

1. We can't tell users "hey, run Enso with this flag and see this project", as it will not work as normal Enso does.
2. This introduces yet another mode of running Enso - this time, without dashboard. This means, that yet another mode needs to be checked during every Q/A, maintained, etc. This adds a lot of trouble.

So, yes, I think we should implement it in such a way, that it will not cause these 2 points above. We can do it in a separate PR ofc :)