Expand armor definition for cestus

[Jarewill]

Summary

Content "Expanded armor definitions for cestus"

Purpose of change

#56338 made me realise that the cestus only covered the fingers while it actually was a hand and arm wrap.
Even the description states that it's "A leather hand and arm wrap"

Describe the solution

Expanded the armor definitions a bit.
I made it cover the entire hand and 60% of the fingers, as it appears to be fingerless most commonly.
Made it so steel only has a 75% coverage on the hands.
And made it cover the forearms with no steel protection.
I also increased it's leather thickness to 2.0 from 1.0, as it's described to be made of hard leather straps.
I based those changes off of this image from wikipedia: https://upload.wikimedia.org/wikipedia/commons/3/3a/Cestus_%28PSF%29.jpg

Describe alternatives you've considered

Leaving the cestus to only cover the fingers.
Buffing it's damage to 3, as 2 feels too little for this weapon and 4 would definitely be overkill.
However I just wanted to change it to cover the arms for now, so the damage remains the same.

Testing

Additional context

This was also done so I could learn how to do advanced armor material definitions. 😄