Add option to expand custom CSS and JS boxes in the View settings

[crbdev]

Is your feature request related to a problem? Please describe.
It can be hard to manage custom CSS and JS code because the editor windows are so small. Users with a lot of custom styles, for example, may have a difficult time managing and editing the code that they add. We previously solved this problem for Custom Content editors by adding an option to expand the modal. I think we should add expanders for these, too.

Describe the solution you'd like
We should consider allowing users to expand these editors by clicking an icon that opens the editor in a large modal.

Describe alternatives you've considered
An alternative solution would be to increase the height of the editor so there's more room to work, or have the height of the editor grow as they add code, up to a certain max height.