Increases XO Police skill by 1 (#6781)

# About the pull request

* Increases the police skill of the XO to SKILL_POLICE_SKILLED from
SKILL_POLICE_FLASH

# Explain why it's good for the game

The XO can choose a MP belt from their own vendor, but cant use most of
the items in it.
Either XO is able to use the MP belt from their own vendor, or the MP
belt gets removed.
But one of those things needs to change, having a noob trap in the XO
role aint cool.


# Testing Photographs and Procedure
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<summary>Screenshots & Videos</summary>

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screenshots and the `<details>` tags.

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# Changelog
:cl:TheManWithNoHands
balance: increases XO police skill by 1

/:cl:

code/datums/skills/uscm.dm

@@ -288,7 +288,7 @@ COMMAND STAFF
 		SKILL_OVERWATCH = SKILL_OVERWATCH_TRAINED,
 		SKILL_MEDICAL = SKILL_MEDICAL_DOCTOR,
 		SKILL_SURGERY = SKILL_SURGERY_NOVICE,
-		SKILL_POLICE = SKILL_POLICE_FLASH,
+		SKILL_POLICE = SKILL_POLICE_SKILLED,
 		SKILL_VEHICLE = SKILL_VEHICLE_SMALL,
 		SKILL_FIREMAN = SKILL_FIREMAN_SKILLED,
 		SKILL_CQC = SKILL_CQC_SKILLED,