feat: new notification provider 46elks

[erlaan]

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Description

This PR adds 46elks as a notification channel for Uptime Kuma

Type of change

• 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

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[CommanderStorm]

Thanks for the PR ♥️
I have left a few suggestions below how this PR can be improved in terms of the UI and code quality.

[erlaan]

Thanks for the PR ♥️ I have left a few suggestions below how this PR can be improved in terms of the UI and code quality.

Thx for the input I think i have fixed all the suggestion now. :)

[CommanderStorm]

Thanks for the new notification provider! 🎉

Note

This PR is part of the v2.0 merge window => see #4500 for the bugs that need to be addressed before we can ship this release ^^

_{All changes in this PR are small and uncontroversial ⇒ merging with junior maintainer approval}