Added Pumble Notification

[cs-jako]

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Description

Notification Provider for Pumble (similar to Slack)

Type of change

Please delete any options that are not relevant.

• New feature (non-breaking change which adds functionality): Notification Provider

Checklist

• My code follows the style guidelines of this project
• I ran ESLint and other linters for modified files
• I have performed a self-review of my own code and tested it
• I have commented my code, particularly in hard-to-understand areas (including JSDoc for methods)
• My changes generates no new warnings
• My code needed automated testing. I have added them (this is optional task)

Screenshots

Event	Screenshot
UP
DOWN
Certificate-expiry
Testing

[CommanderStorm]

Overall, this looks good.
I have left a few changes below. Mostly, could you clairify in a helptext where the webhook url can be found.