[ZeroHeight] Align the spec pages - remove divider

[JeremiasUX]

On a few pages we have a divider and on others not. let's remove the divider and align the design of the spec pages.

Example:

• https://spark.adevinta.com/1186e1705/p/323b83-dropdown
• https://spark.adevinta.com/1186e1705/p/549af2-progress-tracker