New Notification Provider SIGNL4

[rons4]

New notification provider SIGNL4 added.

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Description

This PR adds SIGNL4 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

Screenshots (if any)

Event	Before	After
UP	-
UP	-
DOWN	-
Certificate-expiry	-
Testing	-

[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}

[rons4]

Thank you @CommanderStorm .

The integration page is ready on our side:
https://docs.signl4.com/integrations/uptime-kuma/uptime-kuma.html

I just saw a small spelling mistake in this URL in SIGNL4.vue (uptime-kuima -> uptime-kuma) Shall I open a new PR?

Sorry for this.

We are going to post about the new integration in the next coming days.

[CommanderStorm]

no need for a PR.
Have adjusted the URL in 032ac16

Thanks for the heads up. ^^

On that blog post, please make sure to include a warning that this notification provider is currently waiting for the v2.0 release on the uptime-kuma-side.
Feel free to link to #4500 which users can subscribe to.

I won't be able to get v2.0 ready in the next month (reason: I am on vacation 31.8. - 22.9. and could not get this done beforehand)

PS: The UI looks quite nice from the screenshots. *Tips hat to the UI designer(s) on your team ^^

[rons4]

Perfect. Thanks a lot. I have updated the documentation page including the link:

Thanks also for the UI praise. I will pass it to the team ;-)

Have a great and relaxing vacation.