Workspace Trust layout needs work

[joaomoreno]

Testing #122252

Issues:

• When the layout is too narrow, the green and red boxes are cropped by the editor itself and its contents are basically unreadable
• Also in that same scenario, the scrollbar should be completely aligned to the right margin of the editor. Currently there's some padding which feels weird.
• The scrollbar should also only be visible when the mouse is over the view. It should hide otherwise, like every scrollbar in the workbench.
• The focus border around the Trusted Folders view feels weird, do we even need it?

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Should we place the green and red boxes on top of another, if the space gets too constrained?

[sbatten]

I think the focus border makes sense so I didn't change that, addressed the rest