Adds A New Hair Gradient! (#3849)

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## About The Pull Request
Does exactly what it says on the tin, adding a new hair gradient called
splotches!

![image](https://github.com/user-attachments/assets/3715a606-34df-4911-a20d-bf413030e514)


![image](https://github.com/user-attachments/assets/dd5c09b1-f256-4a79-8f87-6dea03ff33cb)

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## Why It's Good For The Game
I think it looks cute!
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## Changelog

:cl: PositiveEntropy
imageadd: Adds a new hair gradient: Splotches!
/:cl:

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code/modules/mob/dead/new_player/sprite_accessories/hair.dm

@@ -806,3 +806,7 @@
 /datum/sprite_accessory/hair_gradient/long_fade_down
 	name = "Long Fade Down"
 	icon_state = "long_fade_down"
+
+/datum/sprite_accessory/hair_gradient/splotches
+	name = "Splotches"
+	icon_state = "splotches"