Adds station prefixes for Christmas (#76225)

## About The Pull Request

Adds 15 different station prefixes for Christmas, because there were
none previously (why?)

## Why It's Good For The Game


![image](https://github.com/tgstation/tgstation/assets/73006946/4fd9823b-8cd8-48af-a4ec-99e706136c4f)
that's right, why doesn't christmas have special prefixes?
well now it does

## Changelog

🆑
add: Christmas now has special station prefixes.
/🆑

code/modules/holiday/holidays.dm

@@ -659,6 +659,26 @@
 	drone_hat = /obj/item/clothing/head/costume/santa
 	mail_holiday = TRUE
 
+/datum/holiday/xmas/getStationPrefix()
+	return pick(
+		"Bible",
+		"Birthday",
+		"Chimney",
+		"Claus",
+		"Crucifixion",
+		"Elf",
+		"Fir",
+		"Ho Ho Ho",
+		"Jesus",
+		"Jolly",
+		"Merry",
+		"Present",
+		"Sack",
+		"Santa",
+		"Sleigh",
+		"Yule",
+	)
+
 /datum/holiday/xmas/greet()
 	return "Have a merry Christmas!"