Fix unGreet function in npc cassino

[Rechdan]

Description

Just adding npc to the unGreet function, otherwise it would throw an error.

Behaviour

Actual

Errors when ungreeting.

Expected

Ungreet the player.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

How Has This Been Tested

By adding another UnGreet to another NPC and run into that error.

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I checked the PR checks reports
• My changes generate no new warnings