Ticket close reason modal and user messaging

[Vxrpenter]

Etiquette

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Changes

• Bugfix
• Feature
• Behavior Change
• Configuration
• Other: ____

Tested

• Completely
• Mostly
• Partly
• Nothing

Description

• Added a modal for entering a ticket close reason
• Added reason to close message
• Added message that's send to the user containing closing user, channel link and the closing reason
• Small fix to prevent commands being send in private channels