Expand the "Global settings" fieldset when creating new fields

Description of the need

Whenever one creates a new field, the "Global settings" section, which contains the field cardinality setting, is easily overlooked.

So, I attach a field to a node type, then try to create a node of that type, but realize, that I forgot to set the cardinality to a value higher than "1".

Then I go back to the field settings and update the cardinality value, then go back to create a node. ... Some unnecessary clicks in my opinion. I bet, I'm not the only one.

Proposed solution

Expand the fieldset initially, so it's getting a little more attention, when creating fields.

Alternatives that have been considered

Hook form alter... :wink:

There's the fieldset: https://github.com/backdrop/backdrop/blob/1.x/core/modules/field_ui/fiel...