Add a "Do not stack on mobile" toggle on the Columns Block

[mrfoxtalbot]

I have encountered several users confused about their columns stacking on mobile and who were requesting to be able to preserve the original layout.

We could accomplish this by inserting a "Stack on mobile" toggle similar to the one provided in the Media & Text Block, but making it "disabled" by default.

[paaljoachim]

Hey @mrfoxtalbot Alvaro

Here is the visual for Media & Text.

We could add a Stack on mobile that was off by default.

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The issue was brought up during a design triage.
There is hesitation in adding the setting.
It might be better to leave this up to the theme.

[kjellr]

This exists as of Gutenberg 11.1:

Closed via #31816