Add Bitrix24 Webhook notification

[furkanipek]

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Description

Added notification provider using Bitrix24 Webhook.
Resolves #3610

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 generate no new warnings
• My code needed automated testing. I have added them (this is optional task)

Screenshots (if any)

[CommanderStorm]

We also have testing and certificate-expiry notifications as noted in the issue.
Could you provide a screenshot of this case?
You can find expired certs at https://badssl.com/

[furkanipek]

@CommanderStorm Since I took the Telegram Notification files in Uptime Kuma as a reference, I added Bitrix24 without changing the structure.

I am sending screenshots.

[CommanderStorm]

Could you add the following to the description? (this way this issue is not left open once the PR is merged)
Resolves #3610

[furkanipek]

Could you add the following to the description? (this way this issue is not left open once the PR is merged) Resolves #3610

• Ensure that the PR includes screenshots of the DOWN/UP and testing/cert-expiry events.
• All keys that can/should be translated are in en.json (⇒ our translators can translate this and no merge-confilicts between Weblate and master can arise)

[Computroniks]

Changes to the eslint rules in the 2.x branch require that all methods have JSDoc comments. Given that this is a notification provider and as such inherits from the base class, @inheritdoc is sufficient here.

[CommanderStorm]

Re: #3620 (comment)
No, I literally meant please add the string "Resolves #3610" to the description of this Pull Request.
You can read more about linking a pull request to an issue here

[furkanipek]

Could you add the following to the description? (this way this issue is not left open once the PR is merged) Resolves #3610

• Ensure that the PR includes screenshots of the DOWN/UP and testing/cert-expiry events.
• All keys that can/should be translated are in en.json (⇒ our translators can translate this and no merge-confilicts between Weblate and master can arise)

The image I uploaded was wrong, I wrote to inform you.

[CommanderStorm]

Thanks for the new notification provider 🎉

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