Fixes the species behavior of handle_quirk_conflict (#3226)

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## About The Pull Request
The 1 worder changer (real) (not staged)(clickbait)
4 months ago, nefarious creature notices that something isn't behaving
as it should: when species gets changed, the incompatible quirks aren't
removed (horrible), this is because the harddel fixes pr swapped
target_species (which was used to include in-game species changes) for
pref_species

Feel free to scream at me for forgetting to bring this up after writing
it down on my things to do later list:tm:, also you can ask about any
other code that pertains to me if you want and won't contact me
otherwise


![image](https://github.com/user-attachments/assets/6bc56505-1b29-4ff9-9693-e91fd94b0d1b)

This is literally how it happened
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## Why It's Good For The Game
Fixes an issue with the behavior of a proc, which matters for it's use
in line 338 of dna.dm

![image](https://github.com/user-attachments/assets/51a21651-56e9-4b13-adbd-6f7249584849)

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## Changelog

:cl:
fix: fixed handle_quirk_conflict behavior
/:cl:

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code/modules/client/preferences.dm

@@ -1435,7 +1435,7 @@ GLOBAL_LIST_EMPTY(preferences_datums)
 		balance -= initial(quirk_type.value)
 		switch(change_type)
 			if("species")
-				if((quirk_name in SSquirks.species_blacklist) && (pref_species.id in SSquirks.species_blacklist[quirk_name]))
+				if((quirk_name in SSquirks.species_blacklist) && (target_species.id in SSquirks.species_blacklist[quirk_name]))
 					all_quirks_new -= quirk_name
 					balance += initial(quirk_type.value)
 			if("mood")