Add Bale notification provider

[PurTahan]

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Description

Fixes #(issue)

Type of change

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

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 (if any)

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[CommanderStorm]

Code wise this seems really good (no issues that I can spot, there is some autoformatting done by an IDE/.. but nothing bad).

Could you include a screenshot of a message being send to Bale (so we are sure that you have tested it and don't need to spend time setting up this notification provider)?

[PurTahan]

Here is default testing messeage and custum messeages.

[CommanderStorm]

Thanks for the new notification provider! 🎉

Note

This PR is part of the v2.1 merge window and will only be merged once that opens