Changes some parent calls to be cleaner, fixes the thick skin mutation not having proper safety checks

[Gboster-0]

Document the changes in your pull request

Made Thick skin properly check if it was actually added to the DNA before giving its buffs, same with it checking for removal

Changed some if(..())'s with . = ..(); if(.) since its a bit cleaner and if any new mutations get coded in that are children of previous mutations, that can cause the children to always return false on their checks regardless if they were removed or not (not great)

Only touched yogstation files with the above change, as it isn't too big of a deal most of the time, rather its a neat convinience

Why is this good for the game?

Small bug fix gud

Changelog

🆑
bugfix: Thick skin now properly checks if its actually removed before removing its effects
/:cl:

[Oblisk234]

Does this fix #21183, and if so, can you add "Fixes #21183" to your PR description?

[Gboster-0]

Does this fix #21183, and if so, can you add "Fixes #21183" to your PR description?

I got absolutelly no clue