Missing cog Icon in UniconsSolid

[abizareyhan]

There seems to be a discrepancy between the UniconsSolid and UniconsLine icon sets. The UniconsSolid set does not define the cog icon, which results in the following error when trying to use it:

The getter 'cog' isn't defined for the type 'UniconsSolid'.
Try importing the library that defines 'cog', correcting the name to the name of an existing getter, or defining a getter or field named 'cog'.

However, the cog icon is available in the UniconsLine set and works without issues. For reference, you can see the icon here on the Unicons site.

It would be great if the cog icon could be added to the UniconsSolid set for consistency across both icon sets.