RM-14: Per panel ticket limit

[biast12]

Description

RM-14
Per panel ticket limit allows users to set a limit of tickets a user can have open at a time per panel

Related PRs:
TicketsBot-cloud/database#24 - Needs to be pushed before this
TicketsBot-cloud/dashboard#82

Type of Change

• Bug fix
• New feature
• Breaking change

Testing

Set the setting to a ticket limit, check if a non staff user can not create more tickets than the limit, change it and see if it blocks it at that limit, check if the "use global setting" works as it should

Checklist

• My code follows the style of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works