Fix dialogs UI scalability

[AlbyIanna]

Motivation

As explained in #1309, our dialogs might become distorted when scaling up the UI (from the settings or using the shortcut CMD/CTRL + '+').

I've made some fixes in order to make the interface readable and usable with an interface that is scaled up to 200%, with a minimum window size of 450px in width and 300px in height. Maybe they won't look beautiful, but every dialog should be at least usable and readable up to that size.

Change description

Here's a list of screen captures before the changes, with an interface scale of 200% and a window size of 450x300:

Settings dialog

IDE auto-update dialog

Screen.Recording.2022-08-09.at.09.39.43.mov

Select Board dialog

Screen.Recording.2022-08-09.at.09.42.53.mov

WiFi 101/WiFi NINA Firmware Updater dialog

Upload SSL Root Certificates

---

And after the changes:

Settings dialog

Screen.Recording.2022-08-09.at.09.29.03.mov

To avoid the '%' symbol unexpectedly going to a new line, I've added a unitOfMeasure prop to the settings-step-input component: a9ed5b5

IDE auto-update dialog

Screen.Recording.2022-08-09.at.09.37.09.mov

I needed to apply a major refactor on this dialog in order to move the buttons from the content of the dialog (which is the inner react component) to the footer (which is part of the AbstractDialog inherited from Theia): 553c6fe

Select Board dialog

Screen.Recording.2022-08-09.at.09.42.38.mov

Here I've decided to save some space when the size of the window is very small by adding a media query that removes the upper text paragraph on screen heights smaller than 400px: f8f07ea62be6d96191759c89da26c7fb5327c0fff8f07ea62be6d96191759c89da26c7fb5327c0ff

WiFi 101/WiFi NINA Firmware Updater dialog

Upload SSL Root Certificates

Screen.Recording.2022-08-09.at.09.47.55.mov

Other information

Fixes #1309

Reviewer checklist

• PR addresses a single concern.
• The PR has no duplicates (please search among the Pull Requests before creating one)
• PR title and description are properly filled.
• Docs have been added / updated (for bug fixes / features)

[kittaakos]

Thanks for taking the time and making the screencasts about the expected behavior. Very nice 👍

[AlbyIanna]

I've put the PR back in draft because I've decreased the IDE version for testing purposes: 26cbba6

UPDATE:
changes are reverted, PR is ready

[per1234]

Very nice improvements Alberto!