'Amplified' section looks regular-size in deployed app

[mrluc]

With current Livebook (v0.11.1), when I deploy a notebook with an 'Amplified' section, viewing the deployed app doesn't show the full-width 'amplified' view:

[jonatanklosko]

This is expected, amplification is temporary, notice that if you refresh the page it's no longer amplified.

Since this touches on layout, it's related to #2109, which should give more control.

[mrluc]

Super cool, thanks